" Vim syntax file
" Language:	grads (GrADS scripts)
" Maintainer:	Stefan Fronzek (sfronzek at gmx dot net)
" Last change: 13 Feb 2004

" Grid Analysis and Display System (GrADS); http://grads.iges.org/grads
" This syntax file defines highlighting for only very few features of
" the GrADS scripting language.

" For version 5.x: Clear all syntax items
" For version 6.x: Quit when a syntax file was already loaded
if version < 600
  syntax clear
elseif exists("b:current_syntax")
  finish
endif

" GrADS is entirely case-insensitive.
syn case ignore

" The keywords

syn keyword gradsStatement	if else endif break exit return
syn keyword gradsStatement	while endwhile say prompt pull function
syn keyword gradsStatement subwrd sublin substr read write close
" String

syn region gradsString		start=+'+ end=+'+

" Integer number
syn match  gradsNumber		"[+-]\=\<[0-9]\+\>"

" Operator

"syn keyword gradsOperator	| ! % & != >=
"syn match gradsOperator		"[^\.]not[^a-zA-Z]"

" Variables

syn keyword gradsFixVariables	lat lon lev result rec rc
syn match gradsglobalVariables	"_[a-zA-Z][a-zA-Z0-9]*"
syn match gradsVariables		"[a-zA-Z][a-zA-Z0-9]*"
syn match gradsConst		"#[A-Z][A-Z_]+"

" Comments

syn match gradsComment	"\*.*"

" Typical Typos

" for C programmers:
" syn match gradsTypos	"=="
" syn match gradsTypos	"!="

" Define the default highlighting.
" For version 5.7 and earlier: only when not done already
" For version 5.8 and later: only when an item doesn't hgs highlighting+yet
if version >= 508 || !exists("did_gs_syn_inits")
  if version < 508
	let did_gs_syn_inits = 1
	command -nargs=+ HiLink hi link <args>
  else
	command -nargs=+ HiLink hi def link <args>
  endif

  HiLink gradsStatement		Statement

  HiLink gradsString		String
  HiLink gradsNumber		Number

  HiLink gradsFixVariables	Special
  HiLink gradsVariables		Identifier
  HiLink gradsglobalVariables	Special
  HiLink gradsConst		Special

  HiLink gradsClassMethods	Function

  HiLink gradsOperator		Operator
  HiLink gradsComment		Comment

  HiLink gradsTypos		Error

  delcommand HiLink
endif

let b:current_syntax = "grads"