Upload from upload_mods.ps1
This commit is contained in:
Nathaniel Cosford
782
Scripts/Utilities/ExpressionParser/Sprache/Parse.cs
Normal file
782
Scripts/Utilities/ExpressionParser/Sprache/Parse.cs
Normal file
@@ -0,0 +1,782 @@
|
||||
using System;
|
||||
using System.Collections.Generic;
|
||||
using System.Globalization;
|
||||
using UniLinq;
|
||||
|
||||
namespace Sprache
|
||||
{
|
||||
/// <summary>
|
||||
/// Parsers and combinators.
|
||||
/// </summary>
|
||||
public static partial class Parse
|
||||
{
|
||||
/// <summary>
|
||||
/// TryParse a single character matching 'predicate'
|
||||
/// </summary>
|
||||
/// <param name="predicate"></param>
|
||||
/// <param name="description"></param>
|
||||
/// <returns></returns>
|
||||
public static Parser<char> Char(Predicate<char> predicate, string description)
|
||||
{
|
||||
if (predicate == null) throw new ArgumentNullException(nameof(predicate));
|
||||
if (description == null) throw new ArgumentNullException(nameof(description));
|
||||
|
||||
return i =>
|
||||
{
|
||||
if (!i.AtEnd)
|
||||
{
|
||||
if (predicate(i.Current))
|
||||
return Result.Success(i.Current, i.Advance());
|
||||
|
||||
return Result.Failure<char>(i,
|
||||
$"unexpected '{i.Current}'",
|
||||
new[] { description });
|
||||
}
|
||||
|
||||
return Result.Failure<char>(i,
|
||||
"Unexpected end of input reached",
|
||||
new[] { description });
|
||||
};
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Parse a single character except those matching <paramref name="predicate"/>.
|
||||
/// </summary>
|
||||
/// <param name="predicate">Characters not to match.</param>
|
||||
/// <param name="description">Description of characters that don't match.</param>
|
||||
/// <returns>A parser for characters except those matching <paramref name="predicate"/>.</returns>
|
||||
public static Parser<char> CharExcept(Predicate<char> predicate, string description)
|
||||
{
|
||||
return Char(c => !predicate(c), "any character except " + description);
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Parse a single character c.
|
||||
/// </summary>
|
||||
/// <param name="c"></param>
|
||||
/// <returns></returns>
|
||||
public static Parser<char> Char(char c)
|
||||
{
|
||||
return Char(ch => c == ch, char.ToString(c));
|
||||
}
|
||||
|
||||
|
||||
/// <summary>
|
||||
/// Parse a single character of any in c
|
||||
/// </summary>
|
||||
/// <param name="c"></param>
|
||||
/// <returns></returns>
|
||||
public static Parser<char> Chars(params char[] c)
|
||||
{
|
||||
return Char(c.Contains, StringExtensions.Join("|", c));
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Parse a single character of any in c
|
||||
/// </summary>
|
||||
/// <param name="c"></param>
|
||||
/// <returns></returns>
|
||||
public static Parser<char> Chars(string c)
|
||||
{
|
||||
return Char(c.ToEnumerable().Contains, StringExtensions.Join("|", c.ToEnumerable()));
|
||||
}
|
||||
|
||||
|
||||
/// <summary>
|
||||
/// Parse a single character except c.
|
||||
/// </summary>
|
||||
/// <param name="c"></param>
|
||||
/// <returns></returns>
|
||||
public static Parser<char> CharExcept(char c)
|
||||
{
|
||||
return CharExcept(ch => c == ch, char.ToString(c));
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Parses a single character except for those in the given parameters
|
||||
/// </summary>
|
||||
/// <param name="c"></param>
|
||||
/// <returns></returns>
|
||||
public static Parser<char> CharExcept(IEnumerable<char> c)
|
||||
{
|
||||
var chars = c as char[] ?? c.ToArray();
|
||||
return CharExcept(chars.Contains, StringExtensions.Join("|", chars));
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Parses a single character except for those in c
|
||||
/// </summary>
|
||||
/// <param name="c"></param>
|
||||
/// <returns></returns>
|
||||
public static Parser<char> CharExcept(string c)
|
||||
{
|
||||
return CharExcept(c.ToEnumerable().Contains, StringExtensions.Join("|", c.ToEnumerable()));
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Parse a single character in a case-insensitive fashion.
|
||||
/// </summary>
|
||||
/// <param name="c"></param>
|
||||
/// <returns></returns>
|
||||
public static Parser<char> IgnoreCase(char c)
|
||||
{
|
||||
return Char(ch => char.ToLower(c) == char.ToLower(ch), char.ToString(c));
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Parse a string in a case-insensitive fashion.
|
||||
/// </summary>
|
||||
/// <param name="s"></param>
|
||||
/// <returns></returns>
|
||||
public static Parser<IEnumerable<char>> IgnoreCase(string s)
|
||||
{
|
||||
if (s == null) throw new ArgumentNullException(nameof(s));
|
||||
|
||||
return s
|
||||
.ToEnumerable()
|
||||
.Select(IgnoreCase)
|
||||
.Aggregate(Return(Enumerable.Empty<char>()),
|
||||
(a, p) => a.Concat(p.Once()))
|
||||
.Named(s);
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Parse any character.
|
||||
/// </summary>
|
||||
public static readonly Parser<char> AnyChar = Char(c => true, "any character");
|
||||
|
||||
/// <summary>
|
||||
/// Parse a whitespace.
|
||||
/// </summary>
|
||||
public static readonly Parser<char> WhiteSpace = Char(char.IsWhiteSpace, "whitespace");
|
||||
|
||||
/// <summary>
|
||||
/// Parse a digit.
|
||||
/// </summary>
|
||||
public static readonly Parser<char> Digit = Char(char.IsDigit, "digit");
|
||||
|
||||
/// <summary>
|
||||
/// Parse a letter.
|
||||
/// </summary>
|
||||
public static readonly Parser<char> Letter = Char(char.IsLetter, "letter");
|
||||
|
||||
/// <summary>
|
||||
/// Parse a letter or digit.
|
||||
/// </summary>
|
||||
public static readonly Parser<char> LetterOrDigit = Char(char.IsLetterOrDigit, "letter or digit");
|
||||
|
||||
/// <summary>
|
||||
/// Parse a lowercase letter.
|
||||
/// </summary>
|
||||
public static readonly Parser<char> Lower = Char(char.IsLower, "lowercase letter");
|
||||
|
||||
/// <summary>
|
||||
/// Parse an uppercase letter.
|
||||
/// </summary>
|
||||
public static readonly Parser<char> Upper = Char(char.IsUpper, "uppercase letter");
|
||||
|
||||
/// <summary>
|
||||
/// Parse a numeric character.
|
||||
/// </summary>
|
||||
public static readonly Parser<char> Numeric = Char(char.IsNumber, "numeric character");
|
||||
|
||||
/// <summary>
|
||||
/// Parse a string of characters.
|
||||
/// </summary>
|
||||
/// <param name="s"></param>
|
||||
/// <returns></returns>
|
||||
public static Parser<IEnumerable<char>> String(string s)
|
||||
{
|
||||
if (s == null) throw new ArgumentNullException(nameof(s));
|
||||
|
||||
return s
|
||||
.ToEnumerable()
|
||||
.Select(Char)
|
||||
.Aggregate(Return(Enumerable.Empty<char>()),
|
||||
(a, p) => a.Concat(p.Once()))
|
||||
.Named(s);
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Constructs a parser that will fail if the given parser succeeds,
|
||||
/// and will succeed if the given parser fails. In any case, it won't
|
||||
/// consume any input. It's like a negative look-ahead in regex.
|
||||
/// </summary>
|
||||
/// <typeparam name="T">The result type of the given parser</typeparam>
|
||||
/// <param name="parser">The parser to wrap</param>
|
||||
/// <returns>A parser that is the opposite of the given parser.</returns>
|
||||
public static Parser<object> Not<T>(this Parser<T> parser)
|
||||
{
|
||||
if (parser == null) throw new ArgumentNullException(nameof(parser));
|
||||
|
||||
return i =>
|
||||
{
|
||||
var result = parser(i);
|
||||
|
||||
if (result.WasSuccessful)
|
||||
{
|
||||
var msg = $"`{StringExtensions.Join(", ", result.Expectations)}' was not expected";
|
||||
return Result.Failure<object>(i, msg, new string[0]);
|
||||
}
|
||||
return Result.Success<object>(null, i);
|
||||
};
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Parse first, and if successful, then parse second.
|
||||
/// </summary>
|
||||
/// <typeparam name="T"></typeparam>
|
||||
/// <typeparam name="U"></typeparam>
|
||||
/// <param name="first"></param>
|
||||
/// <param name="second"></param>
|
||||
/// <returns></returns>
|
||||
public static Parser<U> Then<T, U>(this Parser<T> first, Func<T, Parser<U>> second)
|
||||
{
|
||||
if (first == null) throw new ArgumentNullException(nameof(first));
|
||||
if (second == null) throw new ArgumentNullException(nameof(second));
|
||||
|
||||
return i => first(i).IfSuccess(s => second(s.Value)(s.Remainder));
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Parse a stream of elements.
|
||||
/// </summary>
|
||||
/// <typeparam name="T"></typeparam>
|
||||
/// <param name="parser"></param>
|
||||
/// <returns></returns>
|
||||
/// <remarks>Implemented imperatively to decrease stack usage.</remarks>
|
||||
public static Parser<IEnumerable<T>> Many<T>(this Parser<T> parser)
|
||||
{
|
||||
if (parser == null) throw new ArgumentNullException(nameof(parser));
|
||||
|
||||
return i =>
|
||||
{
|
||||
var remainder = i;
|
||||
var result = new List<T>();
|
||||
var r = parser(i);
|
||||
|
||||
while (r.WasSuccessful)
|
||||
{
|
||||
if (remainder.Equals(r.Remainder))
|
||||
break;
|
||||
|
||||
result.Add(r.Value);
|
||||
remainder = r.Remainder;
|
||||
r = parser(remainder);
|
||||
}
|
||||
|
||||
return Result.Success<IEnumerable<T>>(result, remainder);
|
||||
};
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Parse a stream of elements, failing if any element is only partially parsed.
|
||||
/// </summary>
|
||||
/// <typeparam name="T">The type of element to parse.</typeparam>
|
||||
/// <param name="parser">A parser that matches a single element.</param>
|
||||
/// <returns>A <see cref="Parser{T}"/> that matches the sequence.</returns>
|
||||
/// <remarks>
|
||||
/// <para>
|
||||
/// Using <seealso cref="XMany{T}(Parser{T})"/> may be preferable to <seealso cref="Many{T}(Parser{T})"/>
|
||||
/// where the first character of each match identified by <paramref name="parser"/>
|
||||
/// is sufficient to determine whether the entire match should succeed. The X*
|
||||
/// methods typically give more helpful errors and are easier to debug than their
|
||||
/// unqualified counterparts.
|
||||
/// </para>
|
||||
/// </remarks>
|
||||
/// <seealso cref="XOr"/>
|
||||
public static Parser<IEnumerable<T>> XMany<T>(this Parser<T> parser)
|
||||
{
|
||||
if (parser == null) throw new ArgumentNullException(nameof(parser));
|
||||
|
||||
return parser.Many().Then(m => parser.Once().XOr(Return(m)));
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// TryParse a stream of elements with at least one item.
|
||||
/// </summary>
|
||||
/// <typeparam name="T"></typeparam>
|
||||
/// <param name="parser"></param>
|
||||
/// <returns></returns>
|
||||
public static Parser<IEnumerable<T>> AtLeastOnce<T>(this Parser<T> parser)
|
||||
{
|
||||
if (parser == null) throw new ArgumentNullException(nameof(parser));
|
||||
|
||||
return parser.Once().Then(t1 => parser.Many().Select(ts => t1.Concat(ts)));
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// TryParse a stream of elements with at least one item. Except the first
|
||||
/// item, all other items will be matched with the <code>XMany</code> operator.
|
||||
/// </summary>
|
||||
/// <typeparam name="T"></typeparam>
|
||||
/// <param name="parser"></param>
|
||||
/// <returns></returns>
|
||||
public static Parser<IEnumerable<T>> XAtLeastOnce<T>(this Parser<T> parser)
|
||||
{
|
||||
if (parser == null) throw new ArgumentNullException(nameof(parser));
|
||||
|
||||
return parser.Once().Then(t1 => parser.XMany().Select(ts => t1.Concat(ts)));
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Parse end-of-input.
|
||||
/// </summary>
|
||||
/// <typeparam name="T"></typeparam>
|
||||
/// <param name="parser"></param>
|
||||
/// <returns></returns>
|
||||
public static Parser<T> End<T>(this Parser<T> parser)
|
||||
{
|
||||
if (parser == null) throw new ArgumentNullException(nameof(parser));
|
||||
|
||||
return i => parser(i).IfSuccess(s =>
|
||||
s.Remainder.AtEnd
|
||||
? s
|
||||
: Result.Failure<T>(
|
||||
s.Remainder,
|
||||
string.Format("unexpected '{0}'", s.Remainder.Current),
|
||||
new[] { "end of input" }));
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Take the result of parsing, and project it onto a different domain.
|
||||
/// </summary>
|
||||
/// <typeparam name="T"></typeparam>
|
||||
/// <typeparam name="U"></typeparam>
|
||||
/// <param name="parser"></param>
|
||||
/// <param name="convert"></param>
|
||||
/// <returns></returns>
|
||||
public static Parser<U> Select<T, U>(this Parser<T> parser, Func<T, U> convert)
|
||||
{
|
||||
if (parser == null) throw new ArgumentNullException(nameof(parser));
|
||||
if (convert == null) throw new ArgumentNullException(nameof(convert));
|
||||
|
||||
return parser.Then(t => Return(convert(t)));
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Parse the token, embedded in any amount of whitespace characters.
|
||||
/// </summary>
|
||||
/// <typeparam name="T"></typeparam>
|
||||
/// <param name="parser"></param>
|
||||
/// <returns></returns>
|
||||
public static Parser<T> Token<T>(this Parser<T> parser)
|
||||
{
|
||||
if (parser == null) throw new ArgumentNullException(nameof(parser));
|
||||
|
||||
return from leading in WhiteSpace.Many()
|
||||
from item in parser
|
||||
from trailing in WhiteSpace.Many()
|
||||
select item;
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Refer to another parser indirectly. This allows circular compile-time dependency between parsers.
|
||||
/// </summary>
|
||||
/// <typeparam name="T"></typeparam>
|
||||
/// <param name="reference"></param>
|
||||
/// <returns></returns>
|
||||
public static Parser<T> Ref<T>(Func<Parser<T>> reference)
|
||||
{
|
||||
if (reference == null) throw new ArgumentNullException(nameof(reference));
|
||||
|
||||
Parser<T> p = null;
|
||||
|
||||
return i =>
|
||||
{
|
||||
if (p == null)
|
||||
p = reference();
|
||||
|
||||
if (i.Memos.ContainsKey(p))
|
||||
{
|
||||
var pResult = i.Memos[p] as IResult<T>;
|
||||
if (pResult.WasSuccessful)
|
||||
return pResult;
|
||||
throw new ParseException(pResult.ToString());
|
||||
}
|
||||
|
||||
i.Memos[p] = Result.Failure<T>(i,
|
||||
"Left recursion in the grammar.",
|
||||
new string[0]);
|
||||
var result = p(i);
|
||||
i.Memos[p] = result;
|
||||
return result;
|
||||
};
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Convert a stream of characters to a string.
|
||||
/// </summary>
|
||||
/// <param name="characters"></param>
|
||||
/// <returns></returns>
|
||||
public static Parser<string> Text(this Parser<IEnumerable<char>> characters)
|
||||
{
|
||||
return characters.Select(chs => new string(chs.ToArray()));
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Parse first, if it succeeds, return first, otherwise try second.
|
||||
/// </summary>
|
||||
/// <typeparam name="T"></typeparam>
|
||||
/// <param name="first"></param>
|
||||
/// <param name="second"></param>
|
||||
/// <returns></returns>
|
||||
public static Parser<T> Or<T>(this Parser<T> first, Parser<T> second)
|
||||
{
|
||||
if (first == null) throw new ArgumentNullException(nameof(first));
|
||||
if (second == null) throw new ArgumentNullException(nameof(second));
|
||||
|
||||
return i =>
|
||||
{
|
||||
var fr = first(i);
|
||||
if (!fr.WasSuccessful)
|
||||
{
|
||||
return second(i).IfFailure(sf => DetermineBestError(fr, sf));
|
||||
}
|
||||
|
||||
if (fr.Remainder.Equals(i))
|
||||
return second(i).IfFailure(sf => fr);
|
||||
|
||||
return fr;
|
||||
};
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Names part of the grammar for help with error messages.
|
||||
/// </summary>
|
||||
/// <typeparam name="T"></typeparam>
|
||||
/// <param name="parser"></param>
|
||||
/// <param name="name"></param>
|
||||
/// <returns></returns>
|
||||
public static Parser<T> Named<T>(this Parser<T> parser, string name)
|
||||
{
|
||||
if (parser == null) throw new ArgumentNullException(nameof(parser));
|
||||
if (name == null) throw new ArgumentNullException(nameof(name));
|
||||
|
||||
return i => parser(i).IfFailure(f => f.Remainder.Equals(i) ?
|
||||
Result.Failure<T>(f.Remainder, f.Message, new[] { name }) :
|
||||
f);
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Parse first, if it succeeds, return first, otherwise try second.
|
||||
/// Assumes that the first parsed character will determine the parser chosen (see Try).
|
||||
/// </summary>
|
||||
/// <typeparam name="T"></typeparam>
|
||||
/// <param name="first"></param>
|
||||
/// <param name="second"></param>
|
||||
/// <returns></returns>
|
||||
public static Parser<T> XOr<T>(this Parser<T> first, Parser<T> second)
|
||||
{
|
||||
if (first == null) throw new ArgumentNullException(nameof(first));
|
||||
if (second == null) throw new ArgumentNullException(nameof(second));
|
||||
|
||||
return i => {
|
||||
var fr = first(i);
|
||||
if (!fr.WasSuccessful)
|
||||
{
|
||||
// The 'X' part
|
||||
if (!fr.Remainder.Equals(i))
|
||||
return fr;
|
||||
|
||||
return second(i).IfFailure(sf => DetermineBestError(fr, sf));
|
||||
}
|
||||
|
||||
// This handles a zero-length successful application of first.
|
||||
if (fr.Remainder.Equals(i))
|
||||
return second(i).IfFailure(sf => fr);
|
||||
|
||||
return fr;
|
||||
};
|
||||
}
|
||||
|
||||
// Examines two results presumably obtained at an "Or" junction; returns the result with
|
||||
// the most information, or if they apply at the same input position, a union of the results.
|
||||
static IResult<T> DetermineBestError<T>(IResult<T> firstFailure, IResult<T> secondFailure)
|
||||
{
|
||||
if (secondFailure.Remainder.Position > firstFailure.Remainder.Position)
|
||||
return secondFailure;
|
||||
|
||||
if (secondFailure.Remainder.Position == firstFailure.Remainder.Position)
|
||||
return Result.Failure<T>(
|
||||
firstFailure.Remainder,
|
||||
firstFailure.Message,
|
||||
firstFailure.Expectations.Union(secondFailure.Expectations));
|
||||
|
||||
return firstFailure;
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Parse a stream of elements containing only one item.
|
||||
/// </summary>
|
||||
/// <typeparam name="T"></typeparam>
|
||||
/// <param name="parser"></param>
|
||||
/// <returns></returns>
|
||||
public static Parser<IEnumerable<T>> Once<T>(this Parser<T> parser)
|
||||
{
|
||||
if (parser == null) throw new ArgumentNullException(nameof(parser));
|
||||
|
||||
return parser.Select(r => (IEnumerable<T>)new[] { r });
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Concatenate two streams of elements.
|
||||
/// </summary>
|
||||
/// <typeparam name="T"></typeparam>
|
||||
/// <param name="first"></param>
|
||||
/// <param name="second"></param>
|
||||
/// <returns></returns>
|
||||
public static Parser<IEnumerable<T>> Concat<T>(this Parser<IEnumerable<T>> first, Parser<IEnumerable<T>> second)
|
||||
{
|
||||
if (first == null) throw new ArgumentNullException(nameof(first));
|
||||
if (second == null) throw new ArgumentNullException(nameof(second));
|
||||
|
||||
return first.Then(f => second.Select(f.Concat));
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Succeed immediately and return value.
|
||||
/// </summary>
|
||||
/// <typeparam name="T"></typeparam>
|
||||
/// <param name="value"></param>
|
||||
/// <returns></returns>
|
||||
public static Parser<T> Return<T>(T value)
|
||||
{
|
||||
return i => Result.Success(value, i);
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Version of Return with simpler inline syntax.
|
||||
/// </summary>
|
||||
/// <typeparam name="T"></typeparam>
|
||||
/// <typeparam name="U"></typeparam>
|
||||
/// <param name="parser"></param>
|
||||
/// <param name="value"></param>
|
||||
/// <returns></returns>
|
||||
public static Parser<U> Return<T, U>(this Parser<T> parser, U value)
|
||||
{
|
||||
if (parser == null) throw new ArgumentNullException(nameof(parser));
|
||||
return parser.Select(t => value);
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Attempt parsing only if the <paramref name="except"/> parser fails.
|
||||
/// </summary>
|
||||
/// <typeparam name="T"></typeparam>
|
||||
/// <typeparam name="U"></typeparam>
|
||||
/// <param name="parser"></param>
|
||||
/// <param name="except"></param>
|
||||
/// <returns></returns>
|
||||
public static Parser<T> Except<T, U>(this Parser<T> parser, Parser<U> except)
|
||||
{
|
||||
if (parser == null) throw new ArgumentNullException(nameof(parser));
|
||||
if (except == null) throw new ArgumentNullException(nameof(except));
|
||||
|
||||
// Could be more like: except.Then(s => s.Fail("..")).XOr(parser)
|
||||
return i =>
|
||||
{
|
||||
var r = except(i);
|
||||
if (r.WasSuccessful)
|
||||
return Result.Failure<T>(i, "Excepted parser succeeded.", new[] { "other than the excepted input" });
|
||||
return parser(i);
|
||||
};
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Parse a sequence of items until a terminator is reached.
|
||||
/// Returns the sequence, discarding the terminator.
|
||||
/// </summary>
|
||||
/// <typeparam name="T"></typeparam>
|
||||
/// <typeparam name="U"></typeparam>
|
||||
/// <param name="parser"></param>
|
||||
/// <param name="until"></param>
|
||||
/// <returns></returns>
|
||||
public static Parser<IEnumerable<T>> Until<T, U>(this Parser<T> parser, Parser<U> until)
|
||||
{
|
||||
return parser.Except(until).Many().Then(r => until.Return(r));
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Succeed if the parsed value matches predicate.
|
||||
/// </summary>
|
||||
/// <typeparam name="T"></typeparam>
|
||||
/// <param name="parser"></param>
|
||||
/// <param name="predicate"></param>
|
||||
/// <returns></returns>
|
||||
public static Parser<T> Where<T>(this Parser<T> parser, Func<T, bool> predicate)
|
||||
{
|
||||
if (parser == null) throw new ArgumentNullException(nameof(parser));
|
||||
if (predicate == null) throw new ArgumentNullException(nameof(predicate));
|
||||
|
||||
return i => parser(i).IfSuccess(s =>
|
||||
predicate(s.Value) ? s : Result.Failure<T>(i,
|
||||
string.Format("Unexpected {0}.", s.Value),
|
||||
new string[0]));
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Monadic combinator Then, adapted for Linq comprehension syntax.
|
||||
/// </summary>
|
||||
/// <typeparam name="T"></typeparam>
|
||||
/// <typeparam name="U"></typeparam>
|
||||
/// <typeparam name="V"></typeparam>
|
||||
/// <param name="parser"></param>
|
||||
/// <param name="selector"></param>
|
||||
/// <param name="projector"></param>
|
||||
/// <returns></returns>
|
||||
public static Parser<V> SelectMany<T, U, V>(
|
||||
this Parser<T> parser,
|
||||
Func<T, Parser<U>> selector,
|
||||
Func<T, U, V> projector)
|
||||
{
|
||||
if (parser == null) throw new ArgumentNullException(nameof(parser));
|
||||
if (selector == null) throw new ArgumentNullException(nameof(selector));
|
||||
if (projector == null) throw new ArgumentNullException(nameof(projector));
|
||||
|
||||
return parser.Then(t => selector(t).Select(u => projector(t, u)));
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Chain a left-associative operator.
|
||||
/// </summary>
|
||||
/// <typeparam name="T"></typeparam>
|
||||
/// <typeparam name="TOp"></typeparam>
|
||||
/// <param name="op"></param>
|
||||
/// <param name="operand"></param>
|
||||
/// <param name="apply"></param>
|
||||
/// <returns></returns>
|
||||
public static Parser<T> ChainOperator<T, TOp>(
|
||||
Parser<TOp> op,
|
||||
Parser<T> operand,
|
||||
Func<TOp, T, T, T> apply)
|
||||
{
|
||||
if (op == null) throw new ArgumentNullException(nameof(op));
|
||||
if (operand == null) throw new ArgumentNullException(nameof(operand));
|
||||
if (apply == null) throw new ArgumentNullException(nameof(apply));
|
||||
return operand.Then(first => ChainOperatorRest(first, op, operand, apply, Or));
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Chain a left-associative operator.
|
||||
/// </summary>
|
||||
/// <typeparam name="T"></typeparam>
|
||||
/// <typeparam name="TOp"></typeparam>
|
||||
/// <param name="op"></param>
|
||||
/// <param name="operand"></param>
|
||||
/// <param name="apply"></param>
|
||||
/// <returns></returns>
|
||||
public static Parser<T> XChainOperator<T, TOp>(
|
||||
Parser<TOp> op,
|
||||
Parser<T> operand,
|
||||
Func<TOp, T, T, T> apply)
|
||||
{
|
||||
if (op == null) throw new ArgumentNullException(nameof(op));
|
||||
if (operand == null) throw new ArgumentNullException(nameof(operand));
|
||||
if (apply == null) throw new ArgumentNullException(nameof(apply));
|
||||
return operand.Then(first => ChainOperatorRest(first, op, operand, apply, XOr));
|
||||
}
|
||||
|
||||
static Parser<T> ChainOperatorRest<T, TOp>(
|
||||
T firstOperand,
|
||||
Parser<TOp> op,
|
||||
Parser<T> operand,
|
||||
Func<TOp, T, T, T> apply,
|
||||
Func<Parser<T>, Parser<T>, Parser<T>> or)
|
||||
{
|
||||
if (op == null) throw new ArgumentNullException(nameof(op));
|
||||
if (operand == null) throw new ArgumentNullException(nameof(operand));
|
||||
if (apply == null) throw new ArgumentNullException(nameof(apply));
|
||||
return or(op.Then(opvalue =>
|
||||
operand.Then(operandValue =>
|
||||
ChainOperatorRest(apply(opvalue, firstOperand, operandValue), op, operand, apply, or))),
|
||||
Return(firstOperand));
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Chain a right-associative operator.
|
||||
/// </summary>
|
||||
/// <typeparam name="T"></typeparam>
|
||||
/// <typeparam name="TOp"></typeparam>
|
||||
/// <param name="op"></param>
|
||||
/// <param name="operand"></param>
|
||||
/// <param name="apply"></param>
|
||||
/// <returns></returns>
|
||||
public static Parser<T> ChainRightOperator<T, TOp>(
|
||||
Parser<TOp> op,
|
||||
Parser<T> operand,
|
||||
Func<TOp, T, T, T> apply)
|
||||
{
|
||||
if (op == null) throw new ArgumentNullException(nameof(op));
|
||||
if (operand == null) throw new ArgumentNullException(nameof(operand));
|
||||
if (apply == null) throw new ArgumentNullException(nameof(apply));
|
||||
return operand.Then(first => ChainRightOperatorRest(first, op, operand, apply, Or));
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Chain a right-associative operator.
|
||||
/// </summary>
|
||||
/// <typeparam name="T"></typeparam>
|
||||
/// <typeparam name="TOp"></typeparam>
|
||||
/// <param name="op"></param>
|
||||
/// <param name="operand"></param>
|
||||
/// <param name="apply"></param>
|
||||
/// <returns></returns>
|
||||
public static Parser<T> XChainRightOperator<T, TOp>(
|
||||
Parser<TOp> op,
|
||||
Parser<T> operand,
|
||||
Func<TOp, T, T, T> apply)
|
||||
{
|
||||
if (op == null) throw new ArgumentNullException(nameof(op));
|
||||
if (operand == null) throw new ArgumentNullException(nameof(operand));
|
||||
if (apply == null) throw new ArgumentNullException(nameof(apply));
|
||||
return operand.Then(first => ChainRightOperatorRest(first, op, operand, apply, XOr));
|
||||
}
|
||||
|
||||
static Parser<T> ChainRightOperatorRest<T, TOp>(
|
||||
T lastOperand,
|
||||
Parser<TOp> op,
|
||||
Parser<T> operand,
|
||||
Func<TOp, T, T, T> apply,
|
||||
Func<Parser<T>, Parser<T>, Parser<T>> or)
|
||||
{
|
||||
if (op == null) throw new ArgumentNullException(nameof(op));
|
||||
if (operand == null) throw new ArgumentNullException(nameof(operand));
|
||||
if (apply == null) throw new ArgumentNullException(nameof(apply));
|
||||
return or(op.Then(opvalue =>
|
||||
operand.Then(operandValue =>
|
||||
ChainRightOperatorRest(operandValue, op, operand, apply, or)).Then(r =>
|
||||
Return(apply(opvalue, lastOperand, r)))),
|
||||
Return(lastOperand));
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Parse a number.
|
||||
/// </summary>
|
||||
public static readonly Parser<string> Number = Numeric.AtLeastOnce().Text();
|
||||
|
||||
static Parser<string> DecimalWithoutLeadingDigits(CultureInfo ci = null)
|
||||
{
|
||||
return from nothing in Return("")
|
||||
// dummy so that CultureInfo.CurrentCulture is evaluated later
|
||||
from dot in String((ci ?? CultureInfo.CurrentCulture).NumberFormat.NumberDecimalSeparator).Text()
|
||||
from fraction in Number
|
||||
select dot + fraction;
|
||||
}
|
||||
|
||||
static Parser<string> DecimalWithLeadingDigits(CultureInfo ci = null)
|
||||
{
|
||||
return Number.Then(n => DecimalWithoutLeadingDigits(ci).XOr(Return("")).Select(f => n + f));
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Parse a decimal number using the current culture's separator character.
|
||||
/// </summary>
|
||||
public static readonly Parser<string> Decimal = DecimalWithLeadingDigits().XOr(DecimalWithoutLeadingDigits());
|
||||
|
||||
/// <summary>
|
||||
/// Parse a decimal number with separator '.'.
|
||||
/// </summary>
|
||||
public static readonly Parser<string> DecimalInvariant = DecimalWithLeadingDigits(CultureInfo.InvariantCulture)
|
||||
.XOr(DecimalWithoutLeadingDigits(CultureInfo.InvariantCulture));
|
||||
}
|
||||
}
|
||||
Reference in New Issue
Block a user