# JSON highlighter per json.org

# Written by Rebecca Turner (@ReBecaOrg)

# Define colors

=Idle
=Comma
=PairSep
=Bracket	magenta
=Brace		magenta
=Number		cyan
=String		cyan
=StringEscape	cyan bold
=Boolean	cyan
=Null		cyan

=Bad		red bold inverse # Syntax errors detected by the highlighter

=ERROR		bold yellow bg_red # Errors in the highlighter itself

:json Idle
	*			end		noeat call=.value()
	" \t\n"			json

:end Idle
	*			endBAD		noeat
	" \t\n"			end

:endBAD Bad
	*			end

.subr value

:value Idle
	*			valueBAD	noeat
	"\""			end		noeat call=.string()
	"-0-9"			end		noeat call=.number()
	"tfn"			end		noeat call=.bareword()
	"{"			end		noeat call=.object()
	"["			end		noeat call=.array()

:valueBAD Bad
	*			value

:end Idle
	*			NULL		noeat return

.end

.subr object

:object Brace
	*			objectBAD	noeat
	"{"			maybeempty

:objectBAD ERROR
	*			end

:maybeempty Brace
	*			key		noeat
	" \t\n"			maybeempty
	"}"			end		recolor=-1

:key Idle
	*			keyBAD		noeat
	"\""			pairsep		noeat call=.string()
	" \t\n"			key

:keyBAD Bad
	*			key

:pairsep PairSep
	*			pairsepBAD	noeat
	":"			value
	" \t\n"			pairsep

:pairsepBAD Bad
	*			pairsep

:value Idle
	*			nextpair	noeat call=.value()
	" \t\n"			value

:nextpair Comma
	*			nextpairBAD	noeat
	"}"			end		recolor=-1
	","			key
	" \t\n"			nextpair

:nextpairBAD Bad
	*			nextpair

:end Brace
	*			NULL		noeat return
.end

.subr array

:array Bracket
	*			arrayBAD	noeat
	"["			maybeempty

:arrayBAD ERROR
	*			end

:maybeempty Bracket
	*			value		noeat
	" \t\n"			maybeempty
	"]"			end		recolor=-1

:value Idle
	*			nextvalue	noeat call=.value()
	" \t\n"			value

:nextvalue Comma
	*			nextvalueBAD	noeat
	"]"			end		recolor=-1
	","			value
	" \t\n"			nextvalue

:nextvalueBAD Bad
	*			nextvalue

:end Bracket
	*			NULL		noeat return

.end

.subr string

:string String
	*			stringBAD	noeat
	"\""			body

:stringBAD ERROR
	*			end

:body String
	*			body
	"\""			end
	"\\"			escape		recolor=-1

:escape StringEscape
	*			escapeBAD	recolor=-2 noeat
	"\"/bfnrt\\"		body
	"u"			unicode1

:escapeBAD Bad
	*			body

:unicode1 StringEscape
	*			unicodeBAD	recolor=-3 noeat
	"0-9a-fA-F"		unicode2

:unicode2 StringEscape
	*			unicodeBAD	recolor=-4 noeat
	"0-9a-fA-F"		unicode3

:unicode3 StringEscape
	*			unicodeBAD	recolor=-5 noeat
	"0-9a-fA-F"		unicode4

:unicode4 StringEscape
	*			unicodeBAD	recolor=-6 noeat
	"0-9a-fA-F"		body

:unicodeBAD Bad
	*			body

:end Idle
	*			NULL		noeat return

.end

.subr bareword

:bareword Idle
	*			body		noeat mark buffer

:body Bad
	*			end		noeat markend strings
	"true"			boolean
	"false"			boolean
	"null"			null
	
done
	"truefalsn"		body

:boolean Boolean
	*			end		noeat

:null Null
	*			end		noeat

:end Idle
	*			NULL		noeat return

.end

.subr number

:number Number
	*			numberBAD
	"0-9"			numberA		noeat
	"-"			numberA

:numberBAD ERROR
	*			end

:numberA Number
	"0"			decimalpoint
	"1-9"			integer

:integer Number
	*			end		noeat
	"0-9"			integer
	"."			decimalpart
	"eE"			exponentpart

:decimalpoint Number
	*			end		noeat
	"0-9"			decimalpointBAD
	"eE"			exponentpart
	"."			decimalpart

:decimalpointBAD Bad
	*			end

:decimalpart Number
	*			decimalpartBAD
	"0-9"			decimalpartA

:decimalpartBAD Bad
	*			end

:decimalpartA Number
	*			end		noeat
	"0-9"			decimalpartA
	"eE"			exponentpart

:exponentpart Number
	*			exponentpartBAD
	"-+"			exponentpartA
	"0-9"			exponentpartB

:exponentpartBAD Bad
	*			end

:exponentpartA Number
	*			exponentpartBAD
	"0-9"			exponentpartB

:exponentpartB Number
	*			end		noeat
	"0-9"			exponentpartB

:end Idle
	*			NULL		noeat return

.end