runtime(erlang): Optimize operators and bitstring types

This commit makes processing the erlangOperator and erlangBitType syntax
items faster.

- erlangOperator changes:
  - Vim now parses erlangOperator faster because we define the operators
    individually.
  - The order of operators in erlangOperator had to be changed to make
    the edge cases work the same as before (for example
    erlangEqualsBinary).
- erlangBitType changes:
  - Vim now parses erlangBitType faster because:
    1. Now the long `\%(integer\|float\|...\)` sections are preceded by
       "beginning of word" patterns (`\<`).
    2. Now we use the old regexp engine (`\%#=1`).

Previously when an Erlang file contained long lines with erlangOperator
or erlangBitType patterns near the end, redrawing these lines was slow,
and typing at the end of the line was also slow.

For example, redrawing a 1787 characters long test line is now roughly
six times faster.

fixes:  #5593
closes: #20524

Signed-off-by: Csaba Hoch <csaba.hoch@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>

diff --git a/runtime/syntax/erlang.vim b/runtime/syntax/erlang.vim
index bbb03d52cdc234a17d0ebf0e546922f89ee07b8f..71084ac1ddc4c0ed6430ee80ba243c7b7bbb7111 100644 (file)
--- a/runtime/syntax/erlang.vim
+++ b/runtime/syntax/erlang.vim
@@ -3,7 +3,7 @@
 " Maintainer:   Csaba Hoch <csaba.hoch@gmail.com>
 " Contributor:  Adam Rutkowski <hq@mtod.org>
 "               Johannes Christ <jc@jchri.st>
-" Last Update:  2025-Nov-12
+" Last Update:  2026-Jun-14
 " License:      Vim license
 " URL:          https://github.com/vim-erlang/vim-erlang-runtime
 
@@ -178,8 +178,38 @@ syn match erlangQuotedAtomModifier '\\\%(\o\{1,3}\|x\x\x\|x{\x\+}\|\^.\|.\)' con
 syn match erlangModifier           '\$\%([^\\]\|\\\%(\o\{1,3}\|x\x\x\|x{\x\+}\|\^.\|.\)\)'
 
 " Operators, separators
-syn match erlangOperator   '==\|=:=\|/=\|=/=\|<\|=<\|>\|>=\|=>\|:=\|?=\|++\|--\|=\|!\|<-\|+\|-\|\*\|\/'
+syn match erlangOperator '='
+syn match erlangOperator '+'
+syn match erlangOperator '-'
+syn match erlangOperator '*'
+syn match erlangOperator '/'
+syn match erlangOperator '<'
+syn match erlangOperator '>'
+syn match erlangOperator '!'
+syn match erlangOperator '=<'
+syn match erlangOperator '>='
+syn match erlangOperator '=>'
+syn match erlangOperator '=='
+syn match erlangOperator '=:='
+syn match erlangOperator '/='
+syn match erlangOperator '=/='
+syn match erlangOperator ':='
+syn match erlangOperator '?='
+syn match erlangOperator '++'
+syn match erlangOperator '--'
+syn match erlangOperator '<-'
+
+" erlangEqualsBinary makes the syntax reflect how Erlang parses the following:
+"
+" A=<<<"binary">>
+"   Valid, same as: A =< <<"binary">>
+" A==<<"binary">>
+"   Valid, same as: A == <<"binary">>
+" A=<<"binary">>
+"   Invalid, parsed as: A =< <"binary">>. This is invalid because there are no
+"   "<<" before the binary, only "<".
 syn match erlangEqualsBinary '=<<\%(<\)\@!'
+
 syn keyword erlangOperator div rem or xor bor bxor bsl bsr and band not bnot andalso orelse
 syn match erlangBracket    '{\|}\|\[\|]\||\|||'
 syn match erlangPipe       '|'
@@ -207,7 +237,7 @@ syn region erlangQuotedRecord        start=/#\s*'/ end=/'/ contains=erlangQuoted
 syn match erlangShebang  '^#!.*'
 
 " Bitstrings
-syn match erlangBitType '\%(\/\%(\s\|\n\|%.*\n\)*\)\@<=\%(integer\|float\|binary\|bytes\|bitstring\|bits\|binary\|utf8\|utf16\|utf32\|signed\|unsigned\|big\|little\|native\|unit\)\%(\%(\s\|\n\|%.*\n\)*-\%(\s\|\n\|%.*\n\)*\%(integer\|float\|binary\|bytes\|bitstring\|bits\|binary\|utf8\|utf16\|utf32\|signed\|unsigned\|big\|little\|native\|unit\)\)*' contains=erlangComment
+syn match erlangBitType '\%#=1\%(\/\%(\s\|\n\|%.*\n\)*\)\@<=\<\%(integer\|float\|binary\|bytes\|bitstring\|bits\|binary\|utf8\|utf16\|utf32\|signed\|unsigned\|big\|little\|native\|unit\)\%(\%(\s\|\n\|%.*\n\)*-\%(\s\|\n\|%.*\n\)*\<\%(integer\|float\|binary\|bytes\|bitstring\|bits\|binary\|utf8\|utf16\|utf32\|signed\|unsigned\|big\|little\|native\|unit\)\)*' contains=erlangComment
 
 " Constants and Directives
 syn match erlangUnknownAttribute '^\s*-\%(\s\|\n\|%.*\n\)*\l[[:alnum:]_@]*' contains=erlangComment