path: root/2020/subtitles/emacsconf-2020--30-a-tour-of-vterm--gabriele-bozzola-sbozzolo-autogen.sbv

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hello and welcome to the stock

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the title of the stock is a tour feature

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a fast and fully featured terminal

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emulator

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inside new e-max so let's try to

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understand what we mean with the pass

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and fully featured

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and to do that we'll compare v term with

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the

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packages which are built in emacs mean

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the term

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so let's let's jump into the v term so

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this is a feature buffer

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and this is a ansi term buffer what i'm

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going to do now is first i'm going to

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prove you

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what we move fast so to do that let me

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open a large file display on screen or

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large file this is about one megabyte of

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data

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and let me time that it takes about 0.6

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seconds

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with feature let's do the same with

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with ancient term well we already

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already see the difference

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so i will use this time to tell you

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what's different and

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what is v term exactly so v term is a

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terminal emulator built

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on top of an external library the

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library is called libvi term

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and is the same library used by newton

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for their own terminal emulator

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it's a c library and this is what gives

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us

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a lot of good features first the speed

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time spent here 0.6 is essentially the

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time that it takes to

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one convert the emax representation of

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like text

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into the visa and representation of what

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was a string and two into

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actually displaying that and that can

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take time

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if there's a if there's quantification

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involved so these are the 0.6 seconds

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there

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as we say in the in ancestor that's much

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much

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more time it's much slower so the

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terminal will feel much snappier much

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faster

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but that's not the main benefit or the

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only benefit of using this external

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library

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feature the second big benefit

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is that v term has support for all the

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escape codes

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that exterm has support for so v term is

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essentially as running x term

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inside an imax buffer so let's see that

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this for example

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let's start by looking at the support

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for colors

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we have support for all the colors out

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of the box we don't have to do anything

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and if we did the same here well we have

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only

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20 colors there's a way to get all the

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colors but it's much more involved

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but this is not where v term shines

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uh we can run all the commands that we

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want

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h top and cdu

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everything runs here also this title

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it's a

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it's a fairly complicated manipulation

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of

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the window and it will not work here

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it just doesn't work actually now the

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terminal is probably messed up

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yes so using this external library

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removes the burden from the developers

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of having to implement

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support for all these cape codes we just

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use those

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so in many ways running veteran

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is us running extern inside a max

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but it's better than that because since

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this is an e-max buffer

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we can enjoy a lot of features from

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emacs

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as well as a tighter integration with

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e-max itself

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for example as you see here the title of

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my buffer

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is from the director i'm in so let's go

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to my tmp

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the title will change so there's

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information being exchanged between v

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term and index

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and of course the title is not the only

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place where information is exchanged

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i can find a file and i will be in the

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directory

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where my terminal is this feature is

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also available in nc term

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and it works also on b term and it

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follows me so if i go to tmp i'll get

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the tmp

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if i ssh to a remote server it will work

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also

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on remote servers as well which is a

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very nice way to edit files remotely

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while we're working on a shelf and

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second while vterm

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is not an e-lisp interpreter like

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initial what we can do is we can

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still run inbox functions so for example

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that requires some configuration the

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term

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command message i as you see there's a

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higher so what i'm doing

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is i'm executing the eagles function i

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and i can drop that

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and turn it around uh hash function to

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run

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a-list functions or another one file see

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we call this feature message passing and

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it requires

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some configuration on the emac side as

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well as in the shell side

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it's important to stress what's the

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nature of feature

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for instance every time i'm sending a

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key binding it's not immediately clear

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if my intention is to send it to the

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shell or to imax so v term implements

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some reasonable defaults

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but at the moment it's mainly packaged

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to display characters on a screen

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so for example if you're using evil the

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editing commands in evil will not work

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immediately there's some work to be done

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and integration can be improved on that

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side but

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sometimes we really want this to behave

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exactly like a imax buffer

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we want to be able to search if

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if i try to get it to search it will not

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work i will send it to the shop so to do

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that

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we enabled the term copy mode so as you

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see

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copy mode and now this buffer is

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essentially a fundamental buffer

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i can move around as i can search

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uh so it must have i

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can do everything i want and there are

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additional features for example i can

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jump around

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all the prompts and i find this

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extremely useful

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because i can copy update from my

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programs or

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what i always have to do is i have to

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google some errors so what i do is i

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select that

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and i have my keybinding in maksakov and

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i'm googling

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what i have to google so this is very

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nice and

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if i now that have selected something if

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i just press return i will

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go back to my normal editing mode with

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the

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text copied so i can paste it back so

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it's a quick way to

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interact with copy and interact with uh

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with the output of a buffer so finally

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let's discuss how to actually

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use beta let's circle back and let's go

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and let's look at the github repo

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where development is happening v term is

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available in velpa

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but since it's leveraging the power of

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an external module

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you must have emacs compiled with

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support for modules

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and many distros like ubuntu debian

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that's not there so you have to get

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emacs with support for modules compiling

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or

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getting images somewhere else and also

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the first time you are going to use this

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which

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works only on mac or

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new linux systems emacs will try to find

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and compile this module

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so it's important this requirement is

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important if you're using windows

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well that's not it's not available and

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will not work

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so to conclude i want to just advertise

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this page

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if you have problems look at the issues

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and

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open unusual in case we'll try to help

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you we are very excited about feature

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and i think it's a transformative

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terminal experience inside glue imax