Added Factor lexer.

Thanks to John Benediktsson.

docs/lexerlist.md

@@ -40,6 +40,7 @@ used if [`fold.scintillua.by.indentation`][] is enabled. For SciTE, see *lexers/
 1. Elm
 1. Erlang`*`
 1. F#
+1. Factor
 1. Fantom`*`
 1. Faust
 1. Fennel

docs/thanks.md

@@ -27,6 +27,7 @@ and better over the years.
 * Ivan Baidakou
 * Jason Schindler
 * Jeff Stone
+* John Benediktsson
 * Jonathon Levi
 * Joseph Eib
 * Joshua Krämer

lexers/factor.lua

@@ -0,0 +1,71 @@
+-- Copyright 2013 Michael T. Richter. See LICENSE.
+-- Copyright 2024 John Benediktsson <mrjbq7@gmail.com>
+-- Factor lexer (http://factorcode.org).
+
+-- At this time the lexer is usable, but not perfect.  Problems include:
+--  * identifiers like (foo) get treated and coloured like stack declarations
+--  * other as-yet unknown display bugs  :-)
+
+local lexer = lexer
+local P, R, S = lpeg.P, lpeg.R, lpeg.S
+
+local lex = lexer.new(...)
+
+-- General building blocks.
+local pre = lexer.upper^1
+local post = pre
+local opt_pre = pre^-1
+local opt_post = opt_pre
+
+-- Comments.
+lex:add_rule('comment', lex:tag(lexer.COMMENT, P('#')^-1 * lexer.to_eol('!')))
+
+-- Strings.
+local dq1_str = opt_pre * lexer.range('"', true)
+lex:add_rule('string', lex:tag(lexer.STRING, dq1_str))
+
+-- Numbers.
+-- Note that complex literals like C{ 1/3 27.3 } are not covered by this lexer.
+-- The C{ ... } notation is treated as an operator--to be specific a
+-- "constructor" (for want of a better term).
+-- Also note that we cannot use lexer.number because numbers do not support the '+' prefix or
+-- case-insensitive base-changing prefixes.
+local hex_digits = lexer.xdigit^1
+local binary = P('-')^-1 * '0b' * S('01')^1
+local octal = P('-')^-1 * '0o' * R('07')^1
+local decimal = P('-')^-1 * lexer.digit^1
+local hexadecimal = P('-')^-1 * '0x' * hex_digits
+local integer = binary + octal + hexadecimal + decimal
+local ratio = decimal * '/' * decimal
+local dfloat_component = decimal * '.' * decimal^-1
+local hfloat_component = hexadecimal * ('.' * hex_digits^-1)^-1
+local float = (dfloat_component * (S('eE') * decimal)^-1) + (hfloat_component * S('pP') * decimal) +
+	(ratio * '.') + (P('-')^-1 * '1/0.') + ('0/0')
+lex:add_rule('number', lex:tag(lexer.NUMBER, (float + ratio + integer)))
+
+-- Keywords.
+-- Things like NAN:, USE:, USING:, POSTPONE:, etc. are considered keywords, as are similar
+-- words that end in #.
+-- Patterns like <<WORD ... WORD>> are similarly considered to be "keywords" (for want of a
+-- better term).
+local colon_words = pre * S(':#') + S(':;')^1
+local angle_words = (P('<')^1 * post) + (pre * P('>')^1)
+lex:add_rule('keyword', lex:tag(lexer.KEYWORD, (colon_words + angle_words)))
+
+-- Operators.
+-- The usual suspects like braces, brackets, angle brackets, parens, etc. are considered to be
+-- operators. They may, however, have prefixes like C{ ... }.
+local constructor_words = opt_pre * S('{[<') + S('}]>') + pre * '(' + ')'
+local stack_declaration = lexer.range('(', ')')
+local other_operators = S('+-*/<>')
+lex:add_rule('operator',
+	lex:tag(lexer.OPERATOR, (stack_declaration + constructor_words + other_operators)))
+
+-- Identifiers.
+-- Identifiers can be practically anything but whitespace.
+local symbols = S('`~!@#$%^&*()_-+={[<>]}:;X,?/')
+lex:add_rule('identifier', lex:tag(lexer.IDENTIFIER, (lexer.alnum + symbols)^1))
+
+lexer.property['factor.comment'] = '!'
+
+return lex

lexers/lexer.lua

@@ -1630,6 +1630,7 @@ function M.detect(filename, line)
 		elm = 'elm', --
 		erl = 'erlang', hrl = 'erlang', --
 		fs = 'fsharp', --
+		factor = 'factor', --
 		fan = 'fantom', --
 		dsp = 'faust', --
 		fnl = 'fennel', --

scintillua.properties

@@ -407,6 +407,17 @@ keywords6.$(file.patterns.fsharp)=scintillua
 keywords7.$(file.patterns.fsharp)=scintillua
 keywords8.$(file.patterns.fsharp)=scintillua
 keywords9.$(file.patterns.fsharp)=scintillua
+file.patterns.factor=*.factor
+lexer.$(file.patterns.factor)=scintillua.factor
+keywords.$(file.patterns.factor)=scintillua
+keywords2.$(file.patterns.factor)=scintillua
+keywords3.$(file.patterns.factor)=scintillua
+keywords4.$(file.patterns.factor)=scintillua
+keywords5.$(file.patterns.factor)=scintillua
+keywords6.$(file.patterns.factor)=scintillua
+keywords7.$(file.patterns.factor)=scintillua
+keywords8.$(file.patterns.factor)=scintillua
+keywords9.$(file.patterns.factor)=scintillua
 file.patterns.fantom=*.fan
 lexer.$(file.patterns.fantom)=scintillua.fantom
 keywords.$(file.patterns.fantom)=scintillua

tests.lua

@@ -1662,6 +1662,31 @@ function test_latex()
 	assert_fold_points(latex, code, folds)
 end
 
+-- Tests Factor lexer.
+function test_factor()
+	local factor = lexer.load('factor')
+
+	local code = [[
+	#!/usr/bin/env factor
+	! comment
+	: foo ( a: integer b -- c )
+	    { 1.5 3/2 1234 1.2e3 } sum + "hello" length sqrt - ;
+	]]
+
+	local tags = {
+		COMMENT, '#!/usr/bin/env factor', --
+		COMMENT, '! comment', --
+		KEYWORD, ':', IDENTIFIER, 'foo', OPERATOR, '( a: integer b -- c )', --
+		OPERATOR, '{', NUMBER, '1.5', NUMBER, '3/2', NUMBER, '1234', NUMBER, '1.2e3', OPERATOR, '}', --
+		IDENTIFIER, 'sum', --
+		OPERATOR, '+', --
+		STRING, '\"hello\"', IDENTIFIER, 'length', IDENTIFIER, 'sqrt', --
+		OPERATOR, '-', --
+		KEYWORD, ';' --
+	}
+	assert_lex(factor, code, tags)
+end
+
 function test_legacy()
 	local lex = lexer.new('test')
 	local ws = lexer.token(lexer.WHITESPACE, lexer.space^1)