WEBVTT
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Hi, my name is Eduardo Ochs.
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I'm this person here,
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and the title of this talk is on "Why
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Most of the Best Features in eev Look
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Like Five Minute Hacks."
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This is a presentation at the
EmacsConf 2020
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happening on November 28 and 29, 2020.
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So this is part one of the presentation.
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Here I'm going to explain
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some ideas that are prerequisites for
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understanding the rest of the
presentation.
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The three main keys of eev are
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M-e, M-k, and M-j.
I'm going to start by
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explaining M-e and M-k.
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M-e is used to follow hyperlinks.
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Technically, it is essentially
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just a C-e to move to
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the end of the line,
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and then a C-x C-e to
execute this,
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the sexp before point at
the end of the line.
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And the thing is that Emacs comes with
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many functions that can be
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used as sexp hyperlinks.
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We can consider that they point to
somewhere.
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I'm going to refer to that as
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the target of the hyperlink.
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If we execute this
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sexp hyperlinks, we coul go to that target.
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For example, this one
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is a hyperlink that points to a buffer
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with the manpage for cat.
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And usually, but not always, after
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following the hyperlink, we can go back
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by just killing the current buffer
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that the hyperlink created:
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the target of the hyperlink.
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But this example here is badly behaved.
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If we execute it, it creates a new frame,
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and to go back to the previous situation,
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we have to either click here
or type C-x 5 0.
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So here are some examples of
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sexp hyperlinks using
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standard Emacs functions.
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This third one is badly behaved
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in a different way.
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If executed, the target is created
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in the same window as we are now,
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but it also shows a lot of
garbage
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here in the echo area,
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so the current frame becomes
a bit messy.
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And well, one of the first things
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that I did when I was creating eev
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many many years ago was that I created
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variants of all these functions
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that were better behaved.
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They were better behaved in two
senses.
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The obvious one was that
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they all created the target
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in the same window as before,
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so I could go back by just typing M-k
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which has essentially just killed this
buffer.
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I also implemented something extra that
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are the postback lists.
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For example, these extra arguments here
are a postback list.
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These extra arguments specify
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position and the target buffer.
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In this example,
this postback list means:
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starting from the beginning of
the buffer,
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search for the first occurrence
of this string after that,
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after the beginning
of the buffer,
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and then search for
the first occurrence
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of this string after that.
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eev also defines some hyperlinks
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that do not create new buffers.
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Here is the first example.
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If I execute this one,
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this one is a hyperlink
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to the result
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of running this show comment date,
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but instead of showing the result
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in the new buffer,
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the result is shown
here.
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So, if I execute this hyperlink,
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the result of date, the output of date,
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is shown in the echo area.
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And if executed again,
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it shows the result again,
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and the result
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changes every second.
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So this is a variant of find-sh.
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find-sh0 is the variant that
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just shows the output in the echo area,
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and find-sh shows the output in
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a new buffer.
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Here is an example of a hyperlink
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that calls an external program.
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If I execute this,
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it calls Google Chrome to open
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a certain URL.
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Here it is. Let's go back to Emacs.
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If I execute this hyperlink here,
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it invokes my favorite PDF viewer
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which is xpdf. It makes xpdf
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open this PDF page. It is PDF
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in this page, and these other arguments
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are ignored. Let me show how it works.
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Here it is. This is an excerpt from a
book.
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So page 3 in the pdf corresponds to
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page 113 in the book.
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This variant here of the hyperlink above,
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it opens the PDF in a different way.
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It runs a program called pdftotext on
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this PDF here,
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and Emacs takes the output of
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running pdftotext on this pdf here
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and displays it in a buffer.
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Now this postback list
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is interpreted in a different way.
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This thing is interpreted
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as a number of a page,
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and Emacs goes to page three
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by counting form feeds in
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the converted version of the PDF
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and then it searches for this string.
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and in this three... So let's execute this
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to see what happens.
Here it is.
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I opened the same page
as before.
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It starts with lecture one.
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So the other hyperlink searched for this
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string and for this string here.
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This thing here is a hyperlink
to video,
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and when I execute it,
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it's going to open this video here
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at this timestamp. Let's see.
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1, 2, 3. 1, 2, 3.
That's the way to do it.
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And also some hyperlinks
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that I defined,
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they don't work like
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usual hyperlinks. They work more
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like browser buttons,
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these buttons that appear in web pages,
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in the sense that these buttons usually
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don't open a new page. They usually
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just do something to change
the current page.
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If I execute this, the action
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of this function eek is to...
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It interprets this string
as a series of keys
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and it acts as if the user had
typed all these keys.
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So if executed, I get a hello
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in the next line.
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If executed again, I get another hello.
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Another hello. hello. hello. etc. etc.
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Let me undo this mess. Oops.
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And here is another kind of button
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that defines a new function. If I execute
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this sexp here, at this moment, though it's
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not defined.
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And if I execute this, Emacs is going to
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show me a message saying
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symbol as function cell is not defined,
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something like this.
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But if I execute the defun,
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the action of this function o here
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is to run this, which opens a certain
directory.
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Let me go back. Here is another
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button that defines
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several functions at the same time.
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If I execute this,
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note that the the result of
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executing this expression
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is the name of one of the functions
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that it defined.
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That is this one here. Let me explain
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these examples. One of the functions
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that this thing here defined
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is called find-orggitfile, where
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this orggit in the middle of its name
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is exactly this first argument to
code-c-d.
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The action of running find-orggitfile
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on a string like this is that
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find-orggitfile takes the string
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and prepends this string to it,
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this one here which is the second
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argument to code-c-d,
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and then it executes find-fline
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on the result, which is this one.
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find-fline is my variant of find-file
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that supports both spec lists.
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This function here that I'm
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referring to as a button,
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it also defines a function called
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find-orggitnode here, where the orggit
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is the same string as here.
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This function opens a node
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of an info manual. This one,
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this text here opens this node
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in the Org manual.
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It is equivalent to this text here.
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So in the passage from this line
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to this line, we prepended
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to the node name the name of
the manual here.
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find-node is my variant
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of this standard Emacs function here,
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but find-node also supports
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postback lists.
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eev also defines some functions that
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define shorter hyperlinks to PDFs
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and videos.
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Remember that this thing here
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is a shorter hyperlink
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to a file. This thing here
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is a shorter hyperlink to a node
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in an Emacs menu in an info manual.
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If we run this thing here, this
code-pdf-page,
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this acts like a button that defines a
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certain function
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and this string,
this other sexp here,
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defines another function.
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The first one defines
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the function find-fongspivak-page,
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and the second one defines the
function find-fongspivak-text.
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When we run the file,
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when we run find-fongspivak-page,
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it opens this PDF here.
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The name is quite long.
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This example opens this PDF at page 8
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and searches for the string contents.
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In this case, it just ignores
this string.
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Here it only considers
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the number of the page. Let's try.
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Here it is, the contents of a book
00:11:45.200 --> 00:11:51.760
that is freely available. Here is
another page of the book.
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And if we execute this
hyperlink here,
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find-fongspivak-text, it converts the
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PDF to text
00:11:59.920 --> 00:12:03.382
and it searches for
page eight in it,
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and then for the string,
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this string here in page eight.
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It takes a few seconds.
00:12:12.240 --> 00:12:16.160
Here it is. So this is the
00:12:16.160 --> 00:12:20.892
ASCII version of this contents page
here.
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Note that this block here
00:12:25.040 --> 00:12:28.800
is a kind of an index to that book.
00:12:28.800 --> 00:12:31.360
I have the full index somewhere,
00:12:31.360 --> 00:12:32.506
but it's very long,
00:12:32.506 --> 00:12:34.959
so I just copied a few lines here.
00:12:34.959 --> 00:12:38.959
So this is a link to s
00:12:38.959 --> 00:12:42.160
section one, chapter one. This is the
00:12:42.160 --> 00:12:48.959
section 1.1, section 1.1.1, and so on.
00:12:48.959 --> 00:12:54.000
Here is a link to the index.
00:12:54.000 --> 00:12:58.079
Here is a part of my index
00:12:58.079 --> 00:13:03.279
of positions in the video
that we just saw
00:13:03.279 --> 00:13:07.360
that I think that are especially
relevant.
00:13:07.360 --> 00:13:11.940
So this hyperlink is a kind
of a button
00:13:11.940 --> 00:13:14.160
that defines this function here,
00:13:14.160 --> 00:13:18.839
find-punchandjudyvideo. Into the video.
00:13:27.600 --> 00:13:30.800
We can also use this for
00:13:30.800 --> 00:13:33.360
video tutorials. For example,
00:13:33.360 --> 00:13:37.200
this is a very good tutorial on Magit.
00:13:37.200 --> 00:13:40.880
If we execute this,
00:13:40.880 --> 00:13:42.560
then these functions are going to be
00:13:42.560 --> 00:13:44.800
defined, and these functions open
00:13:44.800 --> 00:13:48.399
this tutorial on Magit.
00:13:48.399 --> 00:13:50.079
These are some of the positions in the
00:13:50.079 --> 00:13:52.904
tutorial that I found
especially relevant.
00:13:52.904 --> 00:13:54.408
This is a very dense tutorial.
00:13:54.408 --> 00:13:56.480
I had to take notes
of everything,
00:13:56.480 --> 00:13:59.040
and I had to watch everything
00:13:59.040 --> 00:14:00.800
several times.
00:14:00.800 --> 00:14:02.896
For example, this is a link
00:14:02.896 --> 00:14:05.444
to the position in the tutorial
00:14:05.444 --> 00:14:11.005
that explains how in Spacemacs,
00:14:11.005 --> 00:14:17.600
Magit interprets SPC g s as magit-status.
00:14:17.600 --> 00:14:20.480
Let's see. "...beginners.
SPC g s to initiate
00:14:20.480 --> 00:14:22.320
Magit's git status.
00:14:22.320 --> 00:14:25.600
You can also do..." That's it.
00:14:25.600 --> 00:14:28.800
Here are some examples that I
00:14:28.800 --> 00:14:31.200
took from somewhere else.
00:14:31.200 --> 00:14:34.240
The video tutorials from
00:14:34.240 --> 00:14:43.519
Rainer Koenig about Org Mode.
00:14:43.519 --> 00:14:45.308
Now let me show how the functions
00:14:45.308 --> 00:14:47.220
that define these shorter hyperlinks
00:14:47.220 --> 00:14:48.720
are implemented.
00:14:48.720 --> 00:14:50.509
The standard ways in Emacs
00:14:50.509 --> 00:14:53.741
to define functions that define
other functions
00:14:53.741 --> 00:14:55.760
would be with macros.
00:14:55.760 --> 00:14:58.320
Let's see an example. This is a standard
00:14:58.320 --> 00:15:01.540
function that defines new functions.
00:15:02.959 --> 00:15:06.959
If we execute it,
00:15:06.959 --> 00:15:09.040
its result is the last function that it
00:15:09.040 --> 00:15:11.527
defined, which is ee-glyph,
00:15:11.527 --> 00:15:13.920
which is here.
00:15:13.920 --> 00:15:16.959
It's implemented as a macro. We can
00:15:16.959 --> 00:15:20.880
look at the result of macro-expand,
which is going to
00:15:20.880 --> 00:15:22.975
show us the result of this,
00:15:22.975 --> 00:15:25.519
of the expansion of this.
00:15:25.519 --> 00:15:27.804
Instead of expanding and executing,
00:15:27.804 --> 00:15:33.199
it just expands and shows us the result.
00:15:33.199 --> 00:15:35.439
Here the result is a bit messy.
00:15:35.439 --> 00:15:39.396
It's too big for humans to understand,
00:15:39.396 --> 00:15:42.894
but we can run this or this text here.
00:15:42.894 --> 00:15:47.519
That takes that result
and pretty-prints it.
00:15:47.519 --> 00:15:50.701
So this is the pretty-printed version
00:15:50.701 --> 00:15:54.000
of this macro here.
00:15:54.000 --> 00:15:57.600
We can see that it defines
00:15:57.600 --> 00:16:01.120
several functions here.
00:16:01.120 --> 00:16:06.399
For example, this one.
00:16:06.399 --> 00:16:09.360
And this, just as a curiosity, is a link
00:16:09.360 --> 00:16:13.839
to the definition of cl-defstruct.
00:16:13.839 --> 00:16:16.880
Note that the code is huge.
00:16:16.880 --> 00:16:18.677
Well, it's very well-commented,
00:16:18.677 --> 00:16:22.577
but it has lots of special cases.
00:16:22.577 --> 00:16:26.210
It supports lots of constructions,
00:16:26.210 --> 00:16:27.920
and so it's huge.
00:16:27.920 --> 00:16:30.174
It's very difficult to understand.
00:16:30.174 --> 00:16:33.360
I mean, I found it very difficult
to understand.
00:16:33.360 --> 00:16:35.040
Here's a link to document the
00:16:35.040 --> 00:16:37.759
documentation of cl-defstruct
00:16:37.759 --> 00:16:42.210
here in the manual for cl,
00:16:42.210 --> 00:16:45.025
which is a kind of support
00:16:45.025 --> 00:16:50.480
for some features of Common Lisp
in Emacs.
00:16:50.480 --> 00:16:53.825
So let's compare this standard way of
00:16:53.825 --> 00:16:56.560
defining functions that
define new functions,
00:16:56.560 --> 00:16:59.253
which is with macros,
with this.
00:16:59.253 --> 00:17:02.300
I'm going to use a slogan
repeatedly.
00:17:02.300 --> 00:17:06.319
The slogan is: "I am a very bad
programmer."
00:17:06.319 --> 00:17:08.005
I'm a very bad programmer.
00:17:08.005 --> 00:17:10.082
So, when I was trying to create
functions
00:17:10.082 --> 00:17:12.240
that would define new functions,
00:17:12.240 --> 00:17:14.480
I found it easier to generally generate
00:17:14.480 --> 00:17:16.400
this code as text,
00:17:16.400 --> 00:17:20.559
and then run read and eval in it.
00:17:20.559 --> 00:17:24.640
The code-c-d that we saw
in the previous section,
00:17:24.640 --> 00:17:28.079
we can see the code that it produces
00:17:28.079 --> 00:17:30.769
by making a copy of this line
00:17:30.769 --> 00:17:32.579
and prepending this string here
00:17:32.579 --> 00:17:34.480
to the name of the function.
00:17:34.480 --> 00:17:36.317
So, instead of running code-c-d,
00:17:36.317 --> 00:17:38.400
we run find-code-cd,
00:17:38.400 --> 00:17:41.280
and it creates a new temporary buffer
00:17:41.280 --> 00:17:44.400
with the code that
00:17:44.400 --> 00:17:47.760
code-c-d would execute.
00:17:47.760 --> 00:17:54.080
So it's a series of the defuns
and a few setqs and so on.
00:17:54.080 --> 00:17:59.120
And this thing is implemented mostly as
a template.
00:18:02.160 --> 00:18:04.045
There's an inner function called
00:18:04.045 --> 00:18:06.240
ee-code-c-d-base that receives just
00:18:06.240 --> 00:18:08.799
these two arguments, and it says...
00:18:08.799 --> 00:18:10.640
Essentially, it just runs the function
00:18:10.640 --> 00:18:14.320
ee-template0 on the string here, and
00:18:14.320 --> 00:18:16.480
the things between curly braces are
00:18:16.480 --> 00:18:18.559
substituted by the values
00:18:18.559 --> 00:18:23.600
of these arguments here.
00:18:23.600 --> 00:18:25.919
There's one part of the tutorial here
00:18:25.919 --> 00:18:28.480
that explains all these things,
00:18:28.480 --> 00:18:31.039
except for the rationale for some
00:18:31.039 --> 00:18:32.559
design decisions,
00:18:32.559 --> 00:18:35.360
and those design decisions are one of
00:18:35.360 --> 00:18:37.280
the many motivations for this talk.
00:18:37.760 --> 00:18:39.679
I'm only going to explain these
00:18:39.679 --> 00:18:42.640
things in detail at the end,
00:18:42.640 --> 00:18:48.480
which is kind of...
00:18:48.480 --> 00:18:49.662
So in the beginning, I said
00:18:49.662 --> 00:18:51.600
that the three main keys of eev
00:18:51.600 --> 00:18:56.000
are M-e, M-k and M-j.
00:18:56.000 --> 00:19:00.080
Let's see now what M-j does.
00:19:00.080 --> 00:19:02.447
I need to start with some
motivation.
00:19:02.447 --> 00:19:04.640
The motivation is that we
00:19:04.640 --> 00:19:06.559
can define commands with very short
00:19:06.559 --> 00:19:08.240
names. Actually, I became kind of
00:19:08.240 --> 00:19:10.160
addicted to that.
00:19:10.160 --> 00:19:13.200
This is an example of defun that
00:19:13.200 --> 00:19:15.600
defines a comment with a very short name.
00:19:15.600 --> 00:19:18.000
Its name is just one letter, "e."
00:19:18.000 --> 00:19:20.530
and I can invoke... You invoke it
00:19:20.530 --> 00:19:21.856
with M-x e.
00:19:21.856 --> 00:19:24.720
If I type M-x p,
00:19:24.720 --> 00:19:26.661
now it opens a LaTeX file
00:19:26.661 --> 00:19:31.130
that I'm working on.
00:19:32.559 --> 00:19:35.200
I create most of my LaTeX files
00:19:35.200 --> 00:19:39.200
using template-based functions like
00:19:39.200 --> 00:19:43.760
the implementation of code-c-d above.
00:19:43.760 --> 00:19:45.576
These template-based functions
00:19:45.576 --> 00:19:49.280
create files with extension .tex
00:19:49.280 --> 00:19:51.280
that start with a series of defuns
00:19:51.280 --> 00:19:53.919
in comments. For example,
00:19:53.919 --> 00:19:55.926
let's look at this example here.
00:19:55.926 --> 00:19:58.049
If I execute find-latex-links
00:19:58.049 --> 00:19:59.440
with this argument,
00:19:59.440 --> 00:20:02.525
it's going to do several things
00:20:02.525 --> 00:20:08.320
for creating a file called /tmp/foo.tex,
00:20:08.320 --> 00:20:10.387
and the header of that file
00:20:10.387 --> 00:20:12.400
is going to be this,
00:20:12.400 --> 00:20:16.080
which starts with three
00:20:16.080 --> 00:20:19.280
defuns with functions with very short
00:20:19.280 --> 00:20:21.919
names and comments.
00:20:21.919 --> 00:20:27.520
Let's compare with the situation here.
00:20:27.520 --> 00:20:32.799
In my file, 2020favorite-conventions.tex,
00:20:32.799 --> 00:20:34.640
I have this header here in which I
00:20:34.640 --> 00:20:39.360
define six functions with
very short names.
00:20:39.360 --> 00:20:41.919
And in this case here, that is even
00:20:41.919 --> 00:20:44.799
explained in the tutorial.
00:20:44.799 --> 00:20:48.000
These... We have mnemonics for
00:20:48.000 --> 00:20:51.520
these short names here. c is compile,
00:20:51.520 --> 00:20:54.799
d is display. I mean, display the PDF.
00:20:54.799 --> 00:20:57.377
e is added in the sense of
00:20:57.377 --> 00:21:02.320
make Emacs visit that file.
00:21:02.320 --> 00:21:06.480
Now I can explain what is M-j
itself.
00:21:06.480 --> 00:21:09.600
We just saw commands with
very short names.
00:21:09.600 --> 00:21:12.048
The idea behind M-j is that
00:21:12.048 --> 00:21:14.031
we can define commands with
00:21:14.031 --> 00:21:16.480
very short numbers.
00:21:16.480 --> 00:21:19.679
Let me explain this.
00:21:19.679 --> 00:21:23.039
The short explanation
for what M-j does
00:21:23.039 --> 00:21:25.360
is that it jumps to set certain
00:21:25.360 --> 00:21:27.039
predefined places.
00:21:27.039 --> 00:21:30.799
In particular, a M-j without
a numeric argument
00:21:30.799 --> 00:21:32.216
takes us to a buffer
00:21:32.216 --> 00:21:34.080
with the basic help
00:21:34.080 --> 00:21:37.679
and a list of the current jump targets.
00:21:37.679 --> 00:21:39.760
This is something that is a bit
00:21:39.760 --> 00:21:41.520
simpler to understand.
00:21:41.520 --> 00:21:44.559
If we type M-5 M-j,
00:21:44.559 --> 00:21:48.411
then M-j runs this sexp here
00:21:48.411 --> 00:21:51.120
that is associated to
00:21:51.120 --> 00:21:55.440
the argument 5. I say that the target
00:21:55.440 --> 00:21:59.039
for the argument 5 is this one,
00:21:59.039 --> 00:22:01.520
and if the argument is true, then the
00:22:01.520 --> 00:22:03.760
target associated to the true
00:22:03.760 --> 00:22:07.039
is this sexp here that opens...
00:22:07.039 --> 00:22:09.600
This one opens the main tutorial
for eev,
00:22:09.600 --> 00:22:13.679
and this one opens another tutorial.
00:22:13.679 --> 00:22:15.679
This is a link to one of the tutorials
00:22:15.679 --> 00:22:20.480
of eev to the part that explains M-j.
00:22:20.480 --> 00:22:22.212
I've copied the the main part
00:22:22.212 --> 00:22:24.559
of the text here.
00:22:24.559 --> 00:22:28.159
The header that M-j shows...
00:22:28.159 --> 00:22:31.360
Let me show it very quickly here.
00:22:31.360 --> 00:22:36.320
Here is their head and
here is the rest.
00:22:36.320 --> 00:22:38.773
The header is very beginner friendly,
00:22:38.773 --> 00:22:40.000
and if you're a beginner
00:22:40.000 --> 00:22:42.159
who only knows how to use M-e to
00:22:42.159 --> 00:22:44.559
execute and...
00:22:44.559 --> 00:22:46.706
This should be okay.
00:22:46.706 --> 00:22:48.240
M-k to go back.
00:22:48.240 --> 00:22:52.320
Then you can and should use that header--
00:22:52.320 --> 00:22:56.720
I mean, this header here--
00:22:56.720 --> 00:22:58.894
as your main starting point.
00:22:58.894 --> 00:23:00.799
Every time that you feel lost,
00:23:00.799 --> 00:23:04.799
you can type M-j to go back to
that header,
00:23:04.799 --> 00:23:08.000
and you can use its links to
navigate to the documentation
00:23:08.000 --> 00:23:11.360
for Emacs and eev. Let me explain that.
00:23:11.360 --> 00:23:15.679
This header here has several elisp
hyperlinks.
00:23:15.679 --> 00:23:22.400
One here, one here, one here,
one here, and so on.
00:23:22.400 --> 00:23:25.760
These ones are links to the
00:23:25.760 --> 00:23:29.280
to the intros, which are the tutorials.
00:23:29.280 --> 00:23:31.520
find-eev-quick-intro is the
main tutorial,
00:23:31.520 --> 00:23:35.760
and find-emacs-keys-intro is a
kind of tutorial that is
00:23:35.760 --> 00:23:40.000
an index of the main keys.
00:23:40.000 --> 00:23:42.559
After that, we have an explanation of
00:23:42.559 --> 00:23:45.449
what some numeric prefixes do.
00:23:45.449 --> 00:23:49.913
So if we type M-1 M-j,
the effect of that
00:23:49.913 --> 00:23:53.200
is exactly the same as
executing this.
00:23:53.200 --> 00:24:00.159
We can execute this with M-e also.
00:24:00.159 --> 00:24:03.679
M-2 M-j runs this sexp and
00:24:03.679 --> 00:24:06.960
I can also execute it with M-e.
00:24:06.960 --> 00:24:18.400
Here it is. It's this intro, this
sandbox tutorial.
00:24:18.400 --> 00:24:24.640
Here is another sandbox tutorial.
00:24:24.640 --> 00:24:27.039
Let me go back. Then the
00:24:27.039 --> 00:24:29.388
documentation says that header,
00:24:29.388 --> 00:24:31.760
the header that is beginner-friendly
00:24:31.760 --> 00:24:33.679
is followed by a section that is very
00:24:33.679 --> 00:24:35.520
beginner-unfriendly
00:24:35.520 --> 00:24:40.400
that contains a series of defuns
like these ones.
00:24:40.400 --> 00:24:44.640
Here, the last line of the header is
this comment here.
00:24:44.640 --> 00:24:48.559
Then we have several defuns like this.
00:24:48.559 --> 00:24:51.440
Let me explain how these things work.
00:24:51.440 --> 00:24:53.082
Technically, what happens
00:24:53.082 --> 00:24:56.399
when we type M-j without any arguments
00:24:56.399 --> 00:25:00.230
is that it runs eejump with argument nil,
00:25:00.230 --> 00:25:04.640
and then this runs 5 eejumps.
00:25:04.640 --> 00:25:07.224
When I run M-j with a numeric argument,
00:25:07.224 --> 00:25:13.374
for example, with argument 5,
it runs a jump 5.
00:25:13.374 --> 00:25:17.679
eejump-5 concatenates this 5 one
00:25:17.679 --> 00:25:19.999
to make a name of a function,
00:25:19.999 --> 00:25:21.679
this function here.
00:25:21.679 --> 00:25:24.720
and it executes this function
eejump-5.
00:25:24.720 --> 00:25:31.919
You jump -5, and eejump-5
00:25:31.919 --> 00:25:35.520
executes find-eev-quick-intro.
00:25:35.520 --> 00:25:39.360
If I execute just M-j,
00:25:39.360 --> 00:25:40.533
the section that shows
00:25:40.533 --> 00:25:43.919
the current jump targets
00:25:43.919 --> 00:25:46.719
has a line for eejump-5. This is...
00:25:46.719 --> 00:25:52.400
That is exactly the thing
that I was explaining before.
00:25:52.400 --> 00:25:54.544
So we can use M-j to navigate
00:25:54.544 --> 00:25:59.520
the tutorials. We can copy the links.
00:25:59.520 --> 00:26:03.440
Sorry. We can copy links to the
00:26:03.440 --> 00:26:07.919
tutorials to our notes.
00:26:07.919 --> 00:26:11.840
Oh, sorry, this has some typos.
00:26:11.840 --> 00:26:14.880
For example, if I execute this,
00:26:14.880 --> 00:26:18.080
I go to a section of this tutorial here
00:26:18.080 --> 00:26:20.640
that explains the main keys of eev.
00:26:20.640 --> 00:26:23.670
These things are hyperlinks.
00:26:23.670 --> 00:26:25.597
I can mark a hyperlink like this.
00:26:25.597 --> 00:26:27.286
it is just plain text.
00:26:27.286 --> 00:26:29.525
I can copy it to my notes.
00:26:29.525 --> 00:26:31.760
The idea is that every time
00:26:31.760 --> 00:26:34.016
that I find something that is
interesting,
00:26:34.016 --> 00:26:36.240
I can create a hyperlink to it.
00:26:36.240 --> 00:26:38.513
I can put these links in my notes
00:26:38.513 --> 00:26:40.799
so I can navigate back
00:26:40.799 --> 00:26:42.667
to all the interesting positions
00:26:42.667 --> 00:26:48.799
very quickly.
00:26:48.799 --> 00:26:57.600
Okay, next feature.
If we type M-J (uppercase), then
00:26:57.600 --> 00:27:00.080
this is a function that transforms
00:27:00.080 --> 00:27:03.679
the current line in a certain way.
00:27:03.679 --> 00:27:06.471
Let me give an example.
Let me isolate this.
00:27:06.471 --> 00:27:11.039
Let me duplicate this line
to make clear what happens.
00:27:11.039 --> 00:27:14.240
If I type M-J (uppercase) here,
00:27:14.240 --> 00:27:17.561
this line here becomes
the defun for eejump-6,
00:27:17.561 --> 00:27:21.200
and the target of this eejump
00:27:21.200 --> 00:27:24.799
is exactly this sexp here.
00:27:24.799 --> 00:27:28.559
Let me undo this mess.
00:27:28.559 --> 00:27:30.815
If the first word in the line
00:27:30.815 --> 00:27:32.840
is not a number... For example,
00:27:32.840 --> 00:27:36.240
here, let me do the same thing:
00:27:36.240 --> 00:27:41.200
duplicate the line and type M-J,
00:27:41.200 --> 00:27:44.014
then M-J (uppercase) converts that to
00:27:44.014 --> 00:27:49.440
a defun that defines a function
with a very short name.
00:27:49.440 --> 00:27:52.720
This function with a very short name
00:27:52.720 --> 00:27:56.720
opens this file here in the directory
00:27:56.720 --> 00:27:59.360
with the copy of the git repository
00:27:59.360 --> 00:28:01.360
for Org Mode.
00:28:01.360 --> 00:28:05.360
Let me undo the mess again.
00:28:05.360 --> 00:28:14.640
Oops. That's it.
00:28:14.640 --> 00:28:21.279
M-J (uppercase) is a particular case
of something that
00:28:21.279 --> 00:28:23.708
I use a lot in eev.
00:28:23.708 --> 00:28:28.799
eev has lots of commands that--
sorry, key sequences
00:28:28.799 --> 00:28:31.466
that are like M- uppercase letter,
00:28:31.466 --> 00:28:34.660
and almost all of them operate
00:28:34.660 --> 00:28:36.019
on the current line and
00:28:36.019 --> 00:28:37.616
transform the current line
00:28:37.616 --> 00:28:38.880
in a certain way.
00:28:38.880 --> 00:28:42.000
For example, this is a filename.
00:28:42.000 --> 00:28:45.360
If I type M-F (uppercase) here,
00:28:45.360 --> 00:28:47.967
it becomes a link to that file.
00:28:47.967 --> 00:28:50.000
This is the name of a man page.
00:28:50.000 --> 00:28:53.600
If I type M-M (uppercase) here,
00:28:53.600 --> 00:28:55.292
it converts that to the link
00:28:55.292 --> 00:28:58.080
to a manpage. This is a shell command.
00:28:58.080 --> 00:29:01.679
If I type M-S (uppercase) here,
00:29:01.679 --> 00:29:04.960
it converts that to a link to a
00:29:04.960 --> 00:29:08.720
to find-sh (shell).
00:29:08.720 --> 00:29:12.960
Until a few years ago,
these functions
00:29:12.960 --> 00:29:16.159
with M- uppercase letter were half
00:29:16.159 --> 00:29:18.880
of my main ways of creating
sexp hyperlinks
00:29:18.880 --> 00:29:20.085
with a few key strokes.
00:29:20.085 --> 00:29:22.399
In the beginning, of course,
I had to create my
00:29:22.399 --> 00:29:25.600
sexp pipelines by typing each character.
00:29:25.600 --> 00:29:28.640
But after some time, I decided that
00:29:28.640 --> 00:29:31.520
I needed something more efficient.
00:29:31.520 --> 00:29:38.480
So this is the end of part one
of the presentation.
00:29:38.480 --> 00:29:40.640
So this is part two of the presentation,
00:29:40.640 --> 00:29:42.070
and the main theme here
00:29:42.070 --> 00:29:44.320
is the standard describe-key
00:29:44.320 --> 00:29:46.320
function that comes with Emacs.
00:29:46.320 --> 00:29:49.200
My variant of it... The thing is that
00:29:49.200 --> 00:29:50.960
the standard describe-key in Emacs
00:29:50.960 --> 00:29:52.738
is user-friendly, but it is
00:29:52.738 --> 00:29:55.600
hacker-unfriendly. Well, I felt so.
00:29:55.600 --> 00:29:58.281
When I tried to complement it
00:29:58.281 --> 00:30:00.799
by writing a hacker-friendly
version of it
00:30:00.799 --> 00:30:03.919
that produced the sexp hyperlinks
that I needed,
00:30:03.919 --> 00:30:06.457
I got something that
I found really lovely.
00:30:07.039 --> 00:30:08.994
Several of the main
00:30:08.994 --> 00:30:12.480
design decisions of eev can be seen there.
00:30:12.480 --> 00:30:13.995
When I showed my variants to
00:30:13.995 --> 00:30:15.520
other people, they hated it.
00:30:15.520 --> 00:30:16.851
They felt that it was
00:30:16.851 --> 00:30:19.360
totally against their notions of
00:30:19.360 --> 00:30:23.440
user-friendliness.
00:30:23.440 --> 00:30:24.606
Okay. So let's see.
00:30:24.606 --> 00:30:26.297
The standard describe-key,
00:30:26.297 --> 00:30:30.401
if I run this hyperlink here,
I get this.
00:30:30.401 --> 00:30:31.866
The result of running
00:30:31.866 --> 00:30:34.399
describe-key on the key down...
00:30:34.399 --> 00:30:35.799
This is a big buffer
00:30:35.799 --> 00:30:38.080
with some things in italics.
00:30:38.080 --> 00:30:40.752
Some hyperlinks here.
00:30:40.752 --> 00:30:42.387
These hyperlinks are standard
00:30:42.387 --> 00:30:43.679
in the sense that
00:30:43.679 --> 00:30:45.407
the targets are not visible,
00:30:45.407 --> 00:30:47.760
and they are implemented using
00:30:47.760 --> 00:30:49.519
buttons in Emacs Lisp.
00:30:49.519 --> 00:30:52.385
This section of the Emacs Lisp manual
00:30:52.385 --> 00:30:56.799
describes how buttons work.
00:30:56.799 --> 00:31:01.957
The source code is quite difficult.
00:31:01.957 --> 00:31:04.240
I mean, when I was starting to
00:31:04.240 --> 00:31:05.721
to try to decipher this
00:31:05.721 --> 00:31:07.600
when I was a beginner
00:31:07.600 --> 00:31:11.200
using Emacs 19.34, I felt that this
00:31:11.200 --> 00:31:12.320
describe-key was
00:31:12.320 --> 00:31:15.519
very difficult to understand.
00:31:15.519 --> 00:31:20.080
I felt that the the designers,
00:31:20.080 --> 00:31:22.640
the people who wrote it,
were sacrificing
00:31:22.640 --> 00:31:24.839
too much of the hacker-friendliness
00:31:24.839 --> 00:31:27.154
that I was expecting from it
00:31:27.154 --> 00:31:31.279
to make it beginner-friendly.
00:31:31.279 --> 00:31:33.600
Let me explain. What are the problems
00:31:33.600 --> 00:31:35.511
with the standard describe-key?
00:31:35.511 --> 00:31:37.336
If we think that hyperlinks
00:31:37.336 --> 00:31:38.640
are things like this
00:31:38.640 --> 00:31:41.600
with the target and the text, then in the
00:31:41.600 --> 00:31:43.600
button hyperlinks of describe-key,
00:31:43.600 --> 00:31:46.516
these three bad things happen.
00:31:46.516 --> 00:31:49.983
First, it is hard to extract
the target from the hyperlink.
00:31:49.983 --> 00:31:52.000
Second, it is hard to recreate
00:31:52.000 --> 00:31:55.440
a list of code that would
go to that target.
00:31:55.440 --> 00:31:57.519
Third, it is hard to copy the full
00:31:57.519 --> 00:32:00.640
hyperlink, including the targets
to other buffers.
00:32:00.640 --> 00:32:04.960
I only knew how to copy the text
00:32:04.960 --> 00:32:06.937
when I was trying to decipher
00:32:06.937 --> 00:32:09.039
what describe-key was doing.
00:32:09.039 --> 00:32:11.679
I created lots of hyperlinks like this
00:32:11.679 --> 00:32:16.159
to inspect the text properties and
things like that.
00:32:16.159 --> 00:32:18.113
For example, in the description
00:32:18.113 --> 00:32:20.390
of the key down here,
00:32:20.390 --> 00:32:26.799
we have a button that points to
simple.el.
00:32:26.799 --> 00:32:29.336
The text of that button is simple.el.
00:32:29.336 --> 00:32:31.600
This hyperlink goes to the
00:32:31.600 --> 00:32:35.519
to the middle of this
button hyperlink here.
00:32:35.519 --> 00:32:39.120
This hyperlink here
00:32:39.120 --> 00:32:43.279
goes to the middle of the button
of this button hyperlink,
00:32:43.279 --> 00:32:46.240
and then inspects its text properties,
00:32:46.240 --> 00:32:51.679
and then goes to this section here
of the description.
00:32:51.679 --> 00:32:53.521
So this is a high-level description
00:32:53.521 --> 00:32:56.159
of the text properties.
00:32:56.159 --> 00:32:58.782
I mean, the text properties that make it
a button.
00:32:58.782 --> 00:33:04.320
This is a lower-level description of
these text properties.
00:33:04.320 --> 00:33:08.000
The button that points to
00:33:08.000 --> 00:33:11.440
forward-line--sorry, the button
00:33:11.440 --> 00:33:14.399
whose text is forward-line, this one is
00:33:14.399 --> 00:33:16.480
slightly different--
00:33:16.480 --> 00:33:21.200
this hyperlink here goes to the middle
of that button.
00:33:21.200 --> 00:33:25.760
This hyperlink goes to the middle of
that button,
00:33:25.760 --> 00:33:28.173
inspects its text properties,
00:33:28.173 --> 00:33:29.360
and goes to the section
00:33:29.360 --> 00:33:33.617
of this button of this help buffer here
00:33:33.617 --> 00:33:36.399
that describes the button
00:33:36.399 --> 00:33:41.679
and the lower-level view of the text
properties.
00:33:41.679 --> 00:33:45.519
So I started with things like this
00:33:45.519 --> 00:33:47.866
to understand what these buttons
were doing
00:33:47.866 --> 00:33:49.339
and I was able to figure out
00:33:49.339 --> 00:33:51.620
how these things are implemented
00:33:51.620 --> 00:33:53.120
in describe-key, and then
00:33:53.120 --> 00:33:55.519
similar help functions in Emacs.
00:33:55.519 --> 00:33:57.506
I discovered that one of the
00:33:57.506 --> 00:33:59.049
main lower-level functions
00:33:59.049 --> 00:34:01.360
that Emacs used for this
00:34:01.360 --> 00:34:05.279
is a function called
find-function-noselect.
00:34:05.279 --> 00:34:09.929
If I run find-function-noselect
on next line,
00:34:11.200 --> 00:34:14.240
it returns a pair:
00:34:14.240 --> 00:34:18.079
a cons made of a buffer and a position.
00:34:18.079 --> 00:34:20.560
So I created functions that would
00:34:21.679 --> 00:34:24.320
follow this. That would open that
00:34:24.320 --> 00:34:26.510
buffer in that position
00:34:26.510 --> 00:34:29.679
and then this is a postback list.
00:34:29.679 --> 00:34:31.679
So we could go to these positions and
00:34:31.679 --> 00:34:33.919
then search for this string, and another
00:34:33.919 --> 00:34:36.000
string, and another string, and so on.
00:34:36.000 --> 00:34:41.040
So this goes to the definition
of find-efunction
00:34:41.040 --> 00:34:45.006
and then to a string after it.
00:34:45.006 --> 00:34:48.296
I use these things to implement
00:34:48.296 --> 00:34:51.839
my own functions that pointed to the
00:34:51.839 --> 00:34:55.339
same targets as the button hyperlinks
00:34:55.339 --> 00:35:00.240
and describe-key.
00:35:00.240 --> 00:35:02.673
Again, let me show the comparison.
00:35:02.673 --> 00:35:06.322
This is the standard
describe-key here,
00:35:06.322 --> 00:35:10.480
and this is my variant.
00:35:10.480 --> 00:35:13.839
It creates a buffer with links,
00:35:13.839 --> 00:35:17.680
with the list of hyperlinks about this key.
00:35:17.680 --> 00:35:20.960
We get this. So, each one of these
00:35:20.960 --> 00:35:22.960
functions is either a blank line
00:35:22.960 --> 00:35:28.720
or an elisp hyperlink.
00:35:28.720 --> 00:35:34.506
Here is a slight variant of the
function find-ekey-links above.
00:35:34.506 --> 00:35:39.280
In this variant, the argument is a
string that has to be processed by
00:35:39.280 --> 00:35:42.400
read-kbd-macro to convert it to the
00:35:42.400 --> 00:35:45.280
lower-level format.
00:35:45.280 --> 00:35:49.040
Note that these functions here
that I wrote,
00:35:49.040 --> 00:35:50.934
they display temporary buffers
00:35:50.934 --> 00:35:53.599
with no help at all.
00:35:53.599 --> 00:35:57.131
To be honest, there's a link to
00:35:57.131 --> 00:35:58.345
a tutorial here,
00:35:58.345 --> 00:36:00.467
but this is a recent edition
00:36:00.467 --> 00:36:03.200
so let's ignore this.
00:36:03.200 --> 00:36:06.640
They display temporary buffers
00:36:06.640 --> 00:36:07.949
with no help at all,
00:36:07.949 --> 00:36:09.520
just lots of hyperlinks.
00:36:09.520 --> 00:36:11.172
And these hyperlinks can be...
00:36:11.172 --> 00:36:13.359
They are very hacker-friendly
in the sense that
00:36:13.359 --> 00:36:15.477
they can be followed with M-e.
00:36:15.477 --> 00:36:17.520
They can be copied to other
00:36:17.520 --> 00:36:19.920
buffers because they are plain text,
00:36:19.920 --> 00:36:23.680
because they are just sexp.
00:36:23.680 --> 00:36:28.000
And they can be inspected
in the sense that...
00:36:28.000 --> 00:36:32.400
For example, here,
00:36:32.400 --> 00:36:35.520
we have a hyperlink to a function
that we...
00:36:35.520 --> 00:36:37.599
It may be difficult to figure out what
00:36:37.599 --> 00:36:39.200
this function does,
00:36:39.200 --> 00:36:41.600
but we can go to that position,
00:36:41.600 --> 00:36:45.839
and then type C-h f to see the
00:36:45.839 --> 00:36:48.240
description of this function.
00:36:48.240 --> 00:36:53.890
And here is a hyperlink that does that
00:36:56.000 --> 00:37:00.160
in my syntax, say.
00:37:00.160 --> 00:37:02.800
This list of hyperlinks were
00:37:02.800 --> 00:37:08.000
generated by this code here that just
00:37:08.000 --> 00:37:11.119
used a back quote to generate
00:37:11.119 --> 00:37:14.640
lists of sexps.
00:37:14.640 --> 00:37:18.240
I felt that this function here
00:37:18.240 --> 00:37:20.700
that just generated this list
00:37:20.700 --> 00:37:23.393
was very easy to understand
and to modify,
00:37:23.393 --> 00:37:28.480
so this was hacker-friendly
in the way that I wanted.
00:37:28.480 --> 00:37:31.599
So I started using this,
00:37:31.599 --> 00:37:33.459
and this idea of using buffers
00:37:33.459 --> 00:37:36.066
with sexp hyperlinks and no help
00:37:36.066 --> 00:37:38.720
violated all the notions
of user-friendliness
00:37:38.720 --> 00:37:40.079
that I knew, so I was
00:37:40.079 --> 00:37:41.504
exploring something new
00:37:41.504 --> 00:37:46.160
at that time. This is the end of
part two.
00:37:46.160 --> 00:37:49.359
Part three of this presentation is
00:37:49.359 --> 00:37:51.735
about the killer features of eev,
00:37:51.735 --> 00:37:53.778
or why everybody should use eev
00:37:53.778 --> 00:37:55.789
or at least have eev installed
00:37:55.789 --> 00:37:59.280
even if they think that eev
is too weird.
00:37:59.280 --> 00:38:01.200
So this is a very quick listing.
00:38:01.200 --> 00:38:04.240
eev has elisp hyperlinks
which are super nice.
00:38:04.240 --> 00:38:06.050
It comes with lots of tutorials.
00:38:06.050 --> 00:38:10.800
The main one here explains all the
main features.
00:38:10.800 --> 00:38:14.079
There's also a tutorial that's
00:38:14.079 --> 00:38:18.079
an index of all the other tutorials here.
00:38:18.079 --> 00:38:20.509
Many, many, many tutorials.
00:38:20.509 --> 00:38:24.079
If we forget everything,
we can just type M-j.
00:38:24.079 --> 00:38:28.104
Remember that this part here
is beginner-friendly,
00:38:28.104 --> 00:38:32.960
and the rest is
beginner-unfriendly.
00:38:32.960 --> 00:38:38.320
There's a tutorial on Emacs Lisp here.
00:38:38.320 --> 00:38:41.920
It mainly explains how to understand
00:38:41.920 --> 00:38:44.640
Elisp code, which is much easier than...
00:38:44.640 --> 00:38:46.673
It's much easier to understand
Elisp code
00:38:46.673 --> 00:38:50.160
than to understand how to
program in Elisp.
00:38:50.160 --> 00:38:53.440
Most people are only going to need this.
00:38:53.440 --> 00:38:55.368
eev is very easy to install.
00:38:55.368 --> 00:38:58.240
It's in ELPA, so we just need to do
00:38:58.240 --> 00:39:03.520
this thing here, and it's very
non-invasive.
00:39:03.520 --> 00:39:05.472
Years ago, several years ago,
00:39:05.472 --> 00:39:07.039
it was a very invasive package,
00:39:07.039 --> 00:39:08.960
but then I changed everything.
00:39:08.960 --> 00:39:13.520
Now, if we toggle eev-mode on and off,
00:39:13.520 --> 00:39:16.320
what's going to happen is just that
00:39:16.320 --> 00:39:21.599
the eev-keymap becomes activated or
deactivated.
00:39:21.599 --> 00:39:24.720
When we install eev--
00:39:24.720 --> 00:39:27.064
I mean when we require eev,
00:39:27.064 --> 00:39:32.640
the only things that happens globally
are these things here:
00:39:32.640 --> 00:39:34.993
several functions and variables
become defined.
00:39:34.993 --> 00:39:40.079
All of them have standard prefixes,
except for one.
00:39:40.079 --> 00:39:43.040
Three characters are changed in the
00:39:43.040 --> 00:39:44.480
standard display table
00:39:44.480 --> 00:39:48.640
to make them appear as colored glyphs:
00:39:48.640 --> 00:39:52.780
the red star, the open
double angle brackets,
00:39:52.780 --> 00:39:58.160
and the closed double angle brackets.
00:39:58.160 --> 00:40:01.359
Two environment variables are set.
00:40:01.359 --> 00:40:04.560
This is a trivial technicality.
00:40:04.560 --> 00:40:10.800
We just run a defadvice around one
function that is used by "man."
00:40:10.800 --> 00:40:18.400
Also, eev has a very high
discoverability factor.
00:40:18.400 --> 00:40:22.135
There's a way to create,
a very easy way
00:40:22.135 --> 00:40:25.200
to create a hyperlink to here.
00:40:25.200 --> 00:40:27.760
I do not have time to show this now,
00:40:27.760 --> 00:40:31.200
but for example, if I'm here
in a tutorial,
00:40:31.200 --> 00:40:35.736
and I think that this section
is something interesting
00:40:35.736 --> 00:40:39.520
and I want to create a hyperlink to it,
00:40:39.520 --> 00:40:43.040
I just have to type a certain key
sequence here,
00:40:43.040 --> 00:40:45.783
and here I got a hyperlink
00:40:45.783 --> 00:40:48.269
that I can copy to my notes,
00:40:48.269 --> 00:40:52.260
and this hyperlink goes to that section.
00:40:58.240 --> 00:41:02.092
We have hyperlinks that point to
specific positions
00:41:02.092 --> 00:41:05.382
in PDF documents and in video files.
00:41:05.382 --> 00:41:09.119
Here, this one opens a PDF
and displays it.
00:41:09.119 --> 00:41:13.920
This one opens a PDF
and converts it to text.
00:41:13.920 --> 00:41:18.400
and this one opens the video in a
certain position.
00:41:18.400 --> 00:41:20.480
We also have a way to control
00:41:20.480 --> 00:41:22.079
shell-like programs.
00:41:22.079 --> 00:41:25.111
In my presentation of the last year,
00:41:25.111 --> 00:41:28.163
I spent one third of the presentation
explaining this,
00:41:28.163 --> 00:41:31.839
and I think that I gave a very good
demonstration there.
00:41:31.839 --> 00:41:35.680
The demonstration is here.
00:41:35.680 --> 00:41:37.908
We can go to the web page,
00:41:37.908 --> 00:41:41.839
go to this section of the web page,
00:41:41.839 --> 00:41:47.680
and start by this point.
00:41:47.680 --> 00:41:55.920
And here we have an explanation
and so on. Whatever.
00:41:55.920 --> 00:41:58.720
I've already mentioned this before.
00:41:59.200 --> 00:42:02.240
eev comes with a very nice Elisp
tutorial.
00:42:02.240 --> 00:42:05.599
So that's it. This is the end of part
three.
00:42:05.599 --> 00:42:08.103
So this is the last part of my
presentation,
00:42:08.103 --> 00:42:10.965
and it's about the title of the
presentation.
00:42:10.965 --> 00:42:13.599
I called the presentation, "Why
00:42:13.599 --> 00:42:16.560
Most of the Best Features in eev Look
00:42:16.560 --> 00:42:20.480
Like Five-Minute Hacks." I've already
00:42:20.480 --> 00:42:23.920
run out of time, so I have to skip this
00:42:23.920 --> 00:42:28.485
first part here in which
I describe how
00:42:28.485 --> 00:42:33.440
I was exposed to several different
notions of user-friendliness,
00:42:33.440 --> 00:42:35.920
and how the one that really blew my mind
00:42:35.920 --> 00:42:41.680
was the one in a certain
Forth environment.
00:42:41.680 --> 00:42:44.160
Let me make the long, long story
00:42:44.160 --> 00:42:46.560
very, very short.
00:42:46.560 --> 00:42:49.280
In all this process, I switched from
00:42:49.680 --> 00:42:52.960
the belief that the user was always
someone else,
00:42:52.960 --> 00:42:55.359
someone external, and that I always
00:42:55.359 --> 00:42:57.040
had to write my programs for
00:42:57.040 --> 00:43:00.079
this external user. I switched
00:43:00.079 --> 00:43:00.173
from that to the belief
00:43:00.173 --> 00:43:03.200
that I am the user.
00:43:03.200 --> 00:43:06.319
I can play with the interface
that I want.
00:43:06.319 --> 00:43:10.079
I can write programs
00:43:10.079 --> 00:43:11.786
that only I am going to understand.
00:43:11.786 --> 00:43:14.240
I can experiment with
hundreds of interfaces,
00:43:14.240 --> 00:43:16.079
select the best ones,
00:43:16.079 --> 00:43:18.720
document them, and then share them
00:43:18.720 --> 00:43:20.960
with other people
00:43:20.960 --> 00:43:24.056
who are also experimenting
with interfaces
00:43:24.056 --> 00:43:27.050
in their own ways.
00:43:27.050 --> 00:43:30.879
So eev has lots of things
that are user-friendly
00:43:30.879 --> 00:43:34.880
in these unusual ways that I've
explained before.
00:43:34.880 --> 00:43:37.160
If we consider that
00:43:37.160 --> 00:43:40.319
this notion of user-friendliness
is valid,
00:43:40.319 --> 00:43:44.651
then these things that eev implements,
00:43:44.651 --> 00:43:46.904
they are user-friendly
and hacker-friendly
00:43:46.904 --> 00:43:48.800
at the same time.
00:43:48.800 --> 00:43:50.346
Let me show one example.
00:43:51.119 --> 00:43:56.640
This is one that really took me only
five minutes to implement.
00:43:56.640 --> 00:43:59.430
At one point a few months ago,
00:43:59.430 --> 00:44:05.599
I discovered that Sacha Chua's weekly
posts about Emacs News
00:44:05.599 --> 00:44:08.800
were also being posted to a
00:44:08.800 --> 00:44:12.893
mailing list that is stored at
lists.gnu.org,
00:44:12.893 --> 00:44:16.319
and it's called emacs-tangents.
00:44:16.319 --> 00:44:19.760
I found a way to create
00:44:19.760 --> 00:44:25.440
the links to the posts in both places,
00:44:25.440 --> 00:44:28.178
but I had to use a template for that.
00:44:28.178 --> 00:44:30.640
So what we are seeing here now
00:44:30.640 --> 00:44:33.221
is a template with
the default values.
00:44:33.221 --> 00:44:38.243
So this means that we have not set the
year correctly.
00:44:38.243 --> 00:44:40.720
We have not set the month correctly,
00:44:40.720 --> 00:44:42.173
or the day correctly,
00:44:42.173 --> 00:44:45.462
but if we run this sexp here...
00:44:45.462 --> 00:44:48.960
Let me do something else before...
00:44:48.960 --> 00:44:53.359
If we run this sexp here,
00:44:53.359 --> 00:45:00.880
we change some of these entries
00:45:00.880 --> 00:45:05.200
in the template, and we get
these links here.
00:45:05.200 --> 00:45:07.719
They all work. For example,
00:45:07.719 --> 00:45:13.552
this one opens the blog post in
Sacha Chua's site,
00:45:13.552 --> 00:45:21.280
and this one opens it
in the mailing list.
00:45:21.280 --> 00:45:23.672
Sometimes I want
the Org source of that,
00:45:23.672 --> 00:45:26.520
and the easiest way
to get the Org source
00:45:26.520 --> 00:45:31.680
is to look at this link here
that has an attachment.
00:45:31.680 --> 00:45:35.839
If I take this link here,
00:45:35.839 --> 00:45:43.342
and I take this stem that points to the
attachment, and I put it here,
00:45:43.342 --> 00:45:45.440
and I generate this page again
00:45:45.440 --> 00:45:50.000
with all this data,
then I get a script here
00:45:50.000 --> 00:45:51.673
that downloads...
00:45:51.673 --> 00:45:54.640
Let me switch to a smaller font.
00:45:54.640 --> 00:45:58.160
It downloads this attachment
00:45:58.160 --> 00:46:01.599
and it renames that attachment to
something:
00:46:01.599 --> 00:46:06.000
./emacs-news -- sorry, something's...
00:46:06.000 --> 00:46:10.720
-emacs-news-something
00:46:10.720 --> 00:46:15.119
something emacs-news.org here.
00:46:15.119 --> 00:46:16.750
The file is already here,
00:46:16.750 --> 00:46:18.400
already with the right name.
00:46:18.400 --> 00:46:22.079
So I can open it with
just this hyperlink.
00:46:22.079 --> 00:46:23.780
Let me go to the big font again.
00:46:25.200 --> 00:46:28.673
And now I have the Org source
for that hyperlink--
00:46:28.673 --> 00:46:33.839
Sorry, for that blog post.
00:46:33.839 --> 00:46:37.911
And so this one-line thing here
00:46:37.911 --> 00:46:40.960
is, in a sense,
00:46:40.960 --> 00:46:45.119
a hyperlink to this blog post
in all its formats.
00:46:45.119 --> 00:46:48.640
If I execute this, I get links to
00:46:48.640 --> 00:46:52.000
all the places where it is posted,
00:46:52.000 --> 00:46:56.000
and I get a script to
download the local copy
00:46:56.000 --> 00:47:00.480
of the Org source of it. And that's it.
00:47:00.480 --> 00:47:02.506
Well, I'm already out of time,
00:47:02.506 --> 00:47:04.480
so let me finish here.
00:47:04.480 --> 00:47:10.079
Thanks. Bye.
