" Maintainer: Antonio Colombo <antonio.colombo@jrc.it>
" Last Change: 2001 Sep 02
" AWK ref. is: Alfred V. Aho, Brian W. Kernighan, Peter J. Weinberger
" The AWK Programming Language, Addison-Wesley, 1988
" GAWK ref. is: Arnold D. Robbins
" Effective AWK Programming, A User's Guide for GNU Awk
" Edition 1.0.3, Free Software Foundation, 1997
" MAWK is a "new awk" meaning it implements AWK ref.
" mawk conforms to the Posix 1003.2 (draft 11.3)
" definition of the AWK language which contains a few features
" not described in the AWK book, and mawk provides a small number of extensions.
" TODO:
" Dig into the commented out syntax expressions below.
" For version 5.x: Clear all syntax items
" For version 6.x: Quit when a syntax file was already loaded
if version < 600
syn clear
elseif exists("b:current_syntax")
finish
endif
" A bunch of useful Awk keywords
" AWK ref. p. 188
syn keyword awkStatement break continue delete exit
syn keyword awkStatement function getline next
syn keyword awkStatement print printf return
" GAWK ref. p. 268
syn keyword awkStatement nextfile
" AWK ref. p. 42, GAWK ref. p. 272
syn keyword awkFunction atan2 close cos exp int log rand sin sqrt srand
syn keyword awkFunction gsub index length match split sprintf sub
syn keyword awkFunction substr system
" GAWK ref. p. 273-274
syn keyword awkFunction fflush gensub tolower toupper
syn keyword awkFunction systime strftime
syn keyword awkConditional if else
syn keyword awkRepeat while for
syn keyword awkTodo contained TODO
syn keyword awkPatterns BEGIN END
" AWK ref. p. 36
syn keyword awkVariables ARGC ARGV FILENAME FNR FS NF NR
syn keyword awkVariables OFMT OFS ORS RLENGTH RS RSTART SUBSEP
" GAWK ref. p. 260
syn keyword awkVariables ARGIND CONVFMT ENVIRON ERRNO
syn keyword awkVariables FIELDWIDTHS IGNORECASE RT RLENGTH
syn keyword awkRepeat do
" Octal format character.
syn match awkSpecialCharacter display contained "\\[0-7]\{1,3\}"
syn keyword awkStatement func nextfile
" Hex format character.
syn match awkSpecialCharacter display contained "\\x[0-9A-Fa-f]\+"
syn match awkFieldVars "\$\d\+"
"catch errors caused by wrong parenthesis
syn region awkParen transparent start="(" end=")" contains=ALLBUT,awkParenError,awkSpecialCharacter,awkArrayElement,awkArrayArray,awkTodo,awkRegExp,awkBrktRegExp,awkBrackets,awkCharClass
syn match awkParenError display ")"
syn match awkInParen display contained "[{}]"
" 64 lines for complex &&'s, and ||'s in a big "if"
syn sync ccomment awkParen maxlines=64
" Search strings & Regular Expressions therein.
syn region awkSearch oneline start="^[ \t]*/"ms=e start="\(,\|!\=\~\)[ \t]*/"ms=e skip="\\\\\|\\/" end="/" contains=awkBrackets,awkRegExp,awkSpecialCharacter
syn region awkBrackets contained start="\[\^\]\="ms=s+2 start="\[[^\^]"ms=s+1 end="\]"me=e-1 contains=awkBrktRegExp,awkCharClass
syn region awkSearch oneline start="[ \t]*/"hs=e skip="\\\\\|\\/" end="/" contains=awkBrackets,awkRegExp,awkSpecialCharacter
syn match awkCharClass contained "\[:[^:\]]*:\]"
syn match awkBrktRegExp contained "\\.\|.\-[^]]"
syn match awkRegExp contained "/\^"ms=s+1
syn match awkRegExp contained "\$/"me=e-1
syn match awkRegExp contained "[?.*{}|+]"
" String and Character constants
" Highlight special characters (those which have a backslash) differently
syn region awkString start=+"+ skip=+\\\\\|\\"+ end=+"+ contains=awkSpecialCharacter,awkSpecialPrintf
syn match awkSpecialCharacter contained "\\."
" Some of these combinations may seem weird, but they work.
syn match awkSpecialPrintf contained "%[-+ #]*\d*\.\=\d*[cdefgiosuxEGX%]"
" Numbers, allowing signs (both -, and +)
" Integer number.
syn match awkNumber display "[+-]\=\<\d\+\>"
" Floating point number.
syn match awkFloat display "[+-]\=\<\d\+\.\d+\>"
" Floating point number, starting with a dot.
syn match awkFloat display "[+-]\=\<.\d+\>"
syn case ignore
"floating point number, with dot, optional exponent
syn match awkFloat display "\<\d\+\.\d*\(e[-+]\=\d\+\)\=\>"
"floating point number, starting with a dot, optional exponent
syn match awkFloat display "\.\d\+\(e[-+]\=\d\+\)\=\>"
"floating point number, without dot, with exponent
syn match awkFloat display "\<\d\+e[-+]\=\d\+\>"
syn case match
"syn match awkIdentifier "\<[a-zA-Z_][a-zA-Z0-9_]*\>"
" Arithmetic operators: +, and - take care of ++, and --
"syn match awkOperator "+\|-\|\*\|/\|%\|="
"syn match awkOperator "+=\|-=\|\*=\|/=\|%="
"syn match awkOperator "^\|^="
" Comparison expressions.
"syn match awkExpression "==\|>=\|=>\|<=\|=<\|\!="
"syn match awkExpression "\~\|\!\~"
"syn match awkExpression "?\|:"
"syn keyword awkExpression in
" Boolean Logic (OR, AND, NOT)
"syn match awkBoolLogic "||\|&&\|\!"
" This is overridden by less-than & greater-than.
" Put this above those to override them.
" Put this in a 'match "\<printf\=\>.*;\="' to make it not override
" less/greater than (most of the time), but it won't work yet because
" keywords allways have precedence over match & region.
" File I/O: (print foo, bar > "filename") & for nawk (getline < "filename")