vlang(9)

SYNOPSIS

vlang - V programming language

FILES

hkvlang.emf - V programming language hook definition
vlang.eaf - V programming language abbreviation file
vlang.etf - V programming language template file

EXTENSIONS

.v - V-lang

DESCRIPTION

The vlang file type templates share much with the c(9) template definitions, utilising the electric 'C' features for automatic layout of text.

General Editing


On creating a new file, a new header is automatically included into the file. time(2m) is by default enabled, allowing the modification time-stamp to be maintained in the header.

Hilighting


The hilighting features allow commands, variables, logical, preprocessor definitions, comments, strings and characters of the language to be differentiated and rendered in different colors.

Auto Layout


The C-Mode indent(2) performs automatic layout of the text.

restyle-region(3) and restyle-buffer(3) are available to reformat (re-layout) selected sections of the buffer, or the whole buffer, respectively.

Comments may be formatted using esc o, which reformats the comments according to the current fill paragraph. If a comment commences with /***... then the comment is automatically formatted to a box.

Folding and Information Hiding


Generic folding is enabled within the V file. The folds occur about functions defined with the fn keyword and a closing curly brace both at the beginning of a line. collapse-all(3) (un)folds all regions in the file, collapse-current(3) (un)folds the current region.

Navigation via Item List


The V mode offers beside folding as well support for displaying an outline of the functions and structures of the V file for easy navigation using the item-list(3) command. Public functions are highlighted with color in the item list.

Abbreviations


The installation comes with a default abbreviation file for V language file editing which can be used by writing short abbreviations like "for", "if", "elif" (else if), "str" (public structure) or "fn" (function) - and then pressing the key-binding for the expand-abbrev-handle(3) command. The list of abbreviations can be used interactively in the GUI version of MicroEmacs using the abbrev-list(3) command.

Working Environment


compile(3) may be invoked to rebuild the source, the user is prompted to save any files.

Short Cuts


The short cut keys used within the buffer are:

C-c C-c - Comment out the current line.
C-c C-d - Uncomment the current line.
C-c C-e - Comment to the end of the line with stars (*).
A-C-i - Restyle the current region.
esc q - Format a comment.
esc o - Format a comment.
f2 - (Un)fold the current region.
C-f2 - (Un)fold all regions.
f6 - List items.
esc f6 - Close item list,

Executing, Formatting and Linting V Code


The V file hook supports the file-exec(3), the file-format(3) and the file-lint(3) macros. The tools, compilers which are currently supported are just the V sub-commands usable for this task so "v run", "v fmt" and "v vet".

NOTES

The hilighting or the addition of new item list matches is typically extended using a file myvlang.emf.

As this language shares the same extension (.v) as Verilog files there can be a conflict between these two major-modes. MicroEmacs attempts to detect which major mode to use based on the content of the file, but this can go wrong. The best solution to this problem is to add a file content identifier, i.e. add a line like the following to one of the first 2 lines of the file:

// -*- vlang -*- 

Alternatively, if there are no verilog files and you do not wish to edit them, add the following function to your myvlang.emf file:

define-macro ftest-vlang 
  set-variable .result 100 
!emacro 

This will ensure all .v files, without a content identifier, will have vlang major-mode applied.

SEE ALSO

major-mode(2), abbrev-list(3), c(9), collapse-all(3), collapse-current(3), compile(3), expand-abbrev-handle(3), file-exec(3), file-format(3), file-lint(3), item-list(3), restyle-buffer(3), restyle-region(3), time(2m).

Supported File Types

Ref: vlang(9) File: m9typ054.9 Date: 2026/01/18

(c) Copyright JASSPA 2026