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JSON grammars for Perl 6 and for use with JavaCC
/*
* This software is licensed under the terms of the ISC License.
* (ISCL http://www.opensource.org/licenses/isc-license.txt
* It is functionally equivalent to the 2-clause BSD licence,
* with language "made unnecessary by the Berne convention" removed).
*
* Copyright (c) 2011, Mike Norman
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
* SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER
* RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
* NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE
* USE OR PERFORMANCE OF THIS SOFTWARE.
*
*/
options {
STATIC = false;
SUPPORT_CLASS_VISIBILITY_PUBLIC = true;
ERROR_REPORTING = false;
JAVA_UNICODE_ESCAPE = true;
UNICODE_INPUT = true;
NODE_USES_PARSER = false;
VISITOR = false;
}
PARSER_BEGIN(JSONParser)
/*
* This software is licensed under the terms of the ISC License.
* (ISCL http://www.opensource.org/licenses/isc-license.txt
* It is functionally equivalent to the 2-clause BSD licence,
* with language "made unnecessary by the Berne convention" removed).
*
* Copyright (c) 2011, Mike Norman
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
* SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER
* RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
* NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE
* USE OR PERFORMANCE OF THIS SOFTWARE.
*
*/
package org.mwnorman.json;
//javase imports
import java.util.ArrayList;
import java.util.Collections;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
public class JSONParser {
public JSONParser() {
super();
}
}
PARSER_END(JSONParser)
// Pls see http://www.ietf.org/rfc/rfc4627.txt for JSON spec details
// white space
SKIP: {
" "
| "\t"
| "\n"
| "\r"
| "\f"
}
// comments: not really part of JSON spec, but parser shouldn't blow-up if present
SKIP: {
<COMMENT_LINE: "//" (~["\n","\r"])* ("\n"|"\r"|"\r\n")>
}
SKIP: {
<COMMENT_BLOCK: "/*" (~["*"])* "*" ("*" | (~["*","/"] (~["*"])* "*"))* "/">
}
// JSON reserved keywords (prefix with K_ to avoid naming conflicts): only lower case allowed!
TOKEN: {
<K_TRUE: "true">
| <K_FALSE: "false">
| <K_NULL: "null">
}
// JSON operators (prefix with O_ to avoid naming conflicts)
TOKEN: {
<O_OPENBRACE: "{">
| <O_CLOSEBRACE: "}">
| <O_OPENBRACKET: "[">
| <O_CLOSEBRACKET: "]">
| <O_COMMA: ",">
| <O_COLON: ":">
| <O_DOT: ".">
| <O_PLUS: "+">
| <O_MINUS: "-">
}
// numeric literals
TOKEN: {
<#DIGIT: ["0" - "9"] >
| <#NONZERO_DIGIT: ["1" - "9"] >
| <#EXP: ["e", "E"] ( <O_PLUS > | <O_MINUS > )? >
}
// JSON numbers do not support octal or hexadecimal formats
TOKEN: {
<NUMBER: <INTEGER> | <INTEGER> <FRACTIONAL_DIGITS> | <INTEGER> <EXPONENT> | <INTEGER> <FRACTIONAL_DIGITS> <EXPONENT> >
| <INTEGER: (<O_MINUS>)? ( <DIGIT> | <NONZERO_DIGIT> <DIGITS>) >
| <FRACTIONAL_DIGITS: <O_DOT> <DIGITS > >
| <EXPONENT: <EXP> <DIGITS> >
| <DIGITS: ( <DIGIT> )+ >
}
// string literals
TOKEN: {
<STRING: "\"" ( <ALLOWABLE_CHARACTERS> )* "\"" >
| <ALLOWABLE_CHARACTERS:(
(~["\"", "\\", "\u0000"-"\u001f"])
| ("\\"
( ["u"] ["0"-"9","a"-"f", "A"-"F"] ["0"-"9","a"-"f", "A"-"F"] ["0"-"9","a"-"f", "A"-"F"] ["0"-"9","a"-"f", "A"-"F"]
| ["\"", "\\", "b", "f", "n", "r", "t"]
)
)
)
>
}
Object parse() #void:
{
Object o = null;
}
{
( o=object() | o=array() )
{
return o;
}
}
Object object() #void:
{
Map<String, Object> m = new LinkedHashMap<String, Object>();
}
{
<O_OPENBRACE> ( members(m) )? <O_CLOSEBRACE>
{
return m;
}
}
void members(Map<String, Object> m) #void:
{
}
{
pair(m) [ <O_COMMA> members(m) ]
}
void pair(Map<String, Object> m) #void:
{
Token t = null;
Object o;
}
{
t=<STRING> <O_COLON> o=value()
{
m.put(t.image, o);
}
}
Object array() #void:
{
List<Object> a=new ArrayList<Object>();
}
{
<O_OPENBRACKET> ( elements(a) )? <O_CLOSEBRACKET>
{
Collections.reverse(a);
return a;
}
}
void elements(List<Object> a) #void:
{
Object o = null;
}
{
o=value() [ <O_COMMA> elements(a) ]
{
a.add(o);
}
}
Object value() #void:
{
Token t = null;
Object o = null;
}
{
( o=object()
| o=array()
| t=<STRING> {o = t.image;}
| t=<NUMBER>
{
try {
o = Integer.valueOf(t.image);
}
catch (NumberFormatException nfe1) {
try {
o = Long.valueOf(t.image);
}
catch (NumberFormatException nfe2) {
try {
o = Float.valueOf(t.image);
}
catch (NumberFormatException nfe3) {
try {
o = Double.valueOf(t.image);
}
catch (NumberFormatException nfe4) {
o = Double.NaN;
}
}
}
}
}
| <K_TRUE> {o = Boolean.TRUE;}
| <K_FALSE> {o = Boolean.TRUE;}
| <K_NULL> )
{
return o;
}
}
use v6;
grammar JSON::Tiny::Grammar;
rule TOP { ^[ <object> | <array> ]$ }
rule object { '{' ~ '}' <pairlist> }
rule pairlist { [ <pair> ** [ \, ] ]? }
rule pair { <string> ':' <value> }
rule array { '[' ~ ']' [ <value> ** [ \, ] ]? }
proto token value { <...> };
token value:sym<number> {
'-'?
[ 0 | <[1..9]> <[0..9]>* ]
[ \. <[0..9]>+ ]?
[ <[eE]> [\+|\-]? <[0..9]>+ ]?
}
token value:sym<true> { <sym> };
token value:sym<false> { <sym> };
token value:sym<null> { <sym> };
token value:sym<object> { <object> };
token value:sym<array> { <array> };
token value:sym<string> { <string> }
token string {
\" ~ \" ( <str> | \\ <str_escape> )*
}
token str {
[
<!before \t>
<!before \n>
<!before \\>
<!before \">
.
]+
# <-["\\\t\n]>+
}
token str_escape {
<["\\/bfnrt]> | u <xdigit>**4
}
# vim: ft=perl6
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