##// END OF EJS Templates
Bound promise to CancellationToken...
Bound promise to CancellationToken Added new states to ExecutionSate enum. Added Safe.Guard() method to handle cleanup of the result of the promise

File last commit:

r183:4f82e0f161c3 ref20160224
r209:a867536c68fc v2
Show More
JSONGrammar.cs
121 lines | 4.8 KiB | text/x-csharp | CSharpLexer
using System.Linq;
using Implab.Automaton.RegularExpressions;
using System;
using Implab.Automaton;
using Implab.Components;
namespace Implab.Formats.JSON {
class JSONGrammar : Grammar<char> {
public enum TokenType {
None,
BeginObject,
EndObject,
BeginArray,
EndArray,
String,
Number,
Literal,
NameSeparator,
ValueSeparator,
Whitespace,
StringBound,
EscapedChar,
UnescapedChar,
EscapedUnicode
}
static LazyAndWeak<JSONGrammar> _instance = new LazyAndWeak<JSONGrammar>(() => new JSONGrammar());
public static JSONGrammar Instance {
get { return _instance.Value; }
}
readonly ScannerContext<TokenType> m_jsonExpression;
readonly ScannerContext<TokenType> m_stringExpression;
readonly CharAlphabet m_defaultAlphabet = new CharAlphabet();
public JSONGrammar() {
DefineAlphabet(Enumerable.Range(0, 0x20).Select(x => (char)x));
var hexDigit = SymbolRangeToken('a','f').Or(SymbolRangeToken('A','F')).Or(SymbolRangeToken('0','9'));
var digit9 = SymbolRangeToken('1', '9');
var zero = SymbolToken('0');
var digit = zero.Or(digit9);
var dot = SymbolToken('.');
var minus = SymbolToken('-');
var sign = SymbolSetToken('-', '+');
var expSign = SymbolSetToken('e', 'E');
var letters = SymbolRangeToken('a', 'z');
var integer = zero.Or(digit9.Cat(digit.EClosure()));
var frac = dot.Cat(digit.Closure());
var exp = expSign.Cat(sign.Optional()).Cat(digit.Closure());
var quote = SymbolToken('"');
var backSlash = SymbolToken('\\');
var specialEscapeChars = SymbolSetToken('\\', '"', '/', 'b', 'f', 't', 'n', 'r');
var unicodeEspace = SymbolToken('u').Cat(hexDigit.Repeat(4));
var whitespace = SymbolSetToken('\n', '\r', '\t', ' ').EClosure();
var beginObject = whitespace.Cat(SymbolToken('{')).Cat(whitespace);
var endObject = whitespace.Cat(SymbolToken('}')).Cat(whitespace);
var beginArray = whitespace.Cat(SymbolToken('[')).Cat(whitespace);
var endArray = whitespace.Cat(SymbolToken(']')).Cat(whitespace);
var nameSep = whitespace.Cat(SymbolToken(':')).Cat(whitespace);
var valueSep = whitespace.Cat(SymbolToken(',')).Cat(whitespace);
var number = minus.Optional().Cat(integer).Cat(frac.Optional()).Cat(exp.Optional());
var literal = letters.Closure();
var unescaped = SymbolTokenExcept(Enumerable.Range(0, 0x20).Union(new int[] { '\\', '"' }).Select(x => (char)x));
var jsonExpression =
number.Tag(TokenType.Number)
.Or(literal.Tag(TokenType.Literal))
.Or(quote.Tag(TokenType.StringBound))
.Or(beginObject.Tag(TokenType.BeginObject))
.Or(endObject.Tag(TokenType.EndObject))
.Or(beginArray.Tag(TokenType.BeginArray))
.Or(endArray.Tag(TokenType.EndArray))
.Or(nameSep.Tag(TokenType.NameSeparator))
.Or(valueSep.Tag(TokenType.ValueSeparator))
.Or(SymbolSetToken('\n', '\r', '\t', ' ').Closure().Tag(TokenType.Whitespace));
var jsonStringExpression =
quote.Tag(TokenType.StringBound)
.Or(backSlash.Cat(specialEscapeChars).Tag(TokenType.EscapedChar))
.Or(backSlash.Cat(unicodeEspace).Tag(TokenType.EscapedUnicode))
.Or(unescaped.Closure().Tag(TokenType.UnescapedChar));
m_jsonExpression = BuildScannerContext<TokenType>(jsonExpression);
m_stringExpression = BuildScannerContext<TokenType>(jsonStringExpression);
}
protected override IAlphabetBuilder<char> AlphabetBuilder {
get {
return m_defaultAlphabet;
}
}
public ScannerContext<TokenType> JsonExpression {
get {
return m_jsonExpression;
}
}
public ScannerContext<TokenType> JsonStringExpression {
get {
return m_stringExpression;
}
}
Token SymbolRangeToken(char start, char stop) {
return SymbolToken(Enumerable.Range(start, stop - start + 1).Select(x => (char)x));
}
protected override IndexedAlphabetBase<char> CreateAlphabet() {
return new CharAlphabet();
}
}
}