Added optional Lua lexer support.

This support is disabled by default and must be enabled via compile-time option.

1 files changed, 47 insertions, 0 deletions

diff --git a/lexlua/ps.lua b/lexlua/ps.lua
new file mode 100644
index 000000000..a6a211dd7
--- /dev/null
+++ b/lexlua/ps.lua
@@ -0,0 +1,47 @@
+-- Copyright 2006-2018 Mitchell mitchell.att.foicica.com. See License.txt.
+-- Postscript LPeg lexer.
+
+local lexer = require('lexer')
+local token, word_match = lexer.token, lexer.word_match
+local P, R, S = lpeg.P, lpeg.R, lpeg.S
+
+local lex = lexer.new('ps')
+
+-- Whitespace.
+lex:add_rule('whitespace', token(lexer.WHITESPACE, lexer.space^1))
+
+-- Keywords.
+lex:add_rule('keyword', token(lexer.KEYWORD, word_match[[
+  pop exch dup copy roll clear count mark cleartomark counttomark exec if ifelse
+  for repeat loop exit stop stopped countexecstack execstack quit start
+  true false NULL
+]]))
+
+-- Functions.
+lex:add_rule('function', token(lexer.FUNCTION, word_match[[
+  add div idiv mod mul sub abs ned ceiling floor round truncate sqrt atan cos
+  sin exp ln log rand srand rrand
+]]))
+
+-- Identifiers.
+local word = (lexer.alpha + '-') * (lexer.alnum + '-')^0
+lex:add_rule('identifier', token(lexer.IDENTIFIER, word))
+
+-- Strings.
+local arrow_string = lexer.delimited_range('<>')
+local nested_string = lexer.delimited_range('()', false, false, true)
+lex:add_rule('string', token(lexer.STRING, arrow_string + nested_string))
+
+-- Comments.
+lex:add_rule('comment', token(lexer.COMMENT, '%' * lexer.nonnewline^0))
+
+-- Numbers.
+lex:add_rule('number', token(lexer.NUMBER, lexer.float + lexer.integer))
+
+-- Labels.
+lex:add_rule('label', token(lexer.LABEL, '/' * word))
+
+-- Operators.
+lex:add_rule('operator', token(lexer.OPERATOR, S('[]{}')))
+
+return lex