The Vim editor has released their first major release in ten years, Vim 8.0.
This version includes many small features, numerous bug fixes, and the following major highlights:
Asynchronous I/O support, channels
Vim can now exchange messages with other processes in the background. This makes it possible to have servers do work and send back the results to Vim.
Closely related to channels is JSON support. JSON is widely supported and can easily be used for inter-process communication, allowing for writing a server in any language. The functions to use are |json_encode()| and |json_decode()|.
This makes it possible to build very complex plugins, written in any language and running in a separate process.
Jobs
Vim can now start a job, communicate with it and stop it. This is very useful to run a process for completion, syntax checking, etc. Channels are used to communicate with the job. Jobs can also read from or write to a buffer or a file.
Timers
Also asynchronous are timers. They can fire once or repeatedly and invoke a function to do any work. For example:
let tempTimer = timer_start(4000, 'CheckTemp')This will call the CheckTemp() function four seconds (4000 milli seconds) later.
Partials
Vim already had a Funcref, a reference to a function. A partial also refers to a function, and additionally binds arguments and/or a dictionary. This is especially useful for callbacks on channels and timers. E.g., for the timer example above, to pass an argument to the function:
let tempTimer = timer_start(4000, function('CheckTemp', ['out']))This will call CheckTemp(‘out’) four seconds later.
Lambda and Closure
A short way to create a function has been added: {args -> expr}. This is useful for functions such as filter() and map(), which now also accept a function argument. Example:
:call filter(mylist, {idx, val -> val > 20})A lambda can use variables defined in the scope where the lambda is defined. This is usually called a |closure|.
User-defined functions can also be a closure by adding the “closure” argument
:func-closure|Packages
Plugins keep growing and more of them are available than ever before. To keep the collection of plugins manageable package support has been added. This is a convenient way to get one or more plugins, drop them in a directory and possibly keep them updated. Vim will load them automatically, or only when desired.
New style tests
This is for Vim developers. So far writing tests for Vim has not been easy. Vim 8 adds assert functions and a framework to run tests. This makes it a lot simpler to write tests and keep them updated. Also new are several functions that are added specifically for testing.
Window IDs
Previously windows could only be accessed by their number. And every time a window would open, close or move that number changes. Each window now has a unique ID, so that they are easy to find.
Viminfo uses timestamps
Previously the information stored in viminfo was whatever the last Vim wrote there. Now timestamps are used to always keep the most recent items.
Wrapping lines with indent
The ‘breakindent’ option has been added to be able to wrap lines without changing the amount of indent.
Windows: DirectX support
This adds the ‘renderoptions’ option to allow for switching on DirectX (DirectWrite) support on MS-Windows.
GTK+ 3 support
The GTK+ 3 GUI works just like GTK+ 2 except for hardly noticeable technical differences between them. Configure still chooses GTK+ 2 if both 2 and 3 are available.
For more information on this release and for upgrading visit the official Vim site.
