public static IArgument String(CharSource source, ref char chr)
{
var str = new StringBuilder();
while (source.Advance(out chr, true))
{
if (chr == '\\')
{
str.Append(chr);
if (!source.Advance(out chr, true))
{
throw new FinalCharacterException("Expected escaped character after '\\'");
}
str.Append(chr);
}
else if (chr == '"')
{
// If this fails (i.e. the quote is the last character), future calls to skip space will fail
source.Advance(out chr);
return(new StringLiteral()
{
Value = Regex.Unescape(str.ToString())
});
}
else
{
str.Append(chr);
}
}
throw new FinalCharacterException("Expected closing '\"'");
}
public static IArgument TypeName(CharSource source, ref char chr)
{
// Arrive on seeing '/', get collections of names separated by '.'
if (!source.Advance(out chr))
{
throw new FinalCharacterException("Expected type name");
}
var str = new StringBuilder();
while (true)
{
str.Append(source.ReadName(ref chr));
if (chr != '.')
{
return(new TypeNameLiteral()
{
Value = str.ToString()
});
}
str.Append('.');
// We now expect more
if (!source.Advance(out chr))
{
throw new FinalCharacterException("Expected further type name");
}
if (!CharSource.IsNameStart(chr))
{
throw new InvalidCharacterException("Expected name start character: found " + chr);
}
}
}
private static string[] AssignTargets(CharSource source, ref char chr, Dictionary <string, IFunction> funcs)
{
// Seen '='
if (!source.Advance(out chr))
{
throw new FinalCharacterException("Expected assignment token, \"=>\"");
}
else if (chr != '>')
{
throw new InvalidCharacterException($"Expected assignment token, \"=>\": found \"={chr}\"");
}
if (!source.AdvanceWhiteSpace(out chr))
{
throw new FinalCharacterException("Expected assignment");
}
var right = Arguments.Multiple(source, ref chr, funcs).Evaluate();
if (!right.All(t => t is NameArgument))
{
throw new InvalidArgumentException($"Assigned types must be names");
}
var names = right.Select(t => (t as NameArgument).Value).ToArray();
return(names);
}
public static IArgument Function(CharSource source, ref char chr, Dictionary <string, IFunction> funcs)
{
// Arrive here having seen '('
if (!source.AdvanceWhiteSpace(out chr))
{
throw new FinalCharacterException("Expected a function name");
}
var name = Arguments.Single(source, ref chr, funcs);
if (!(name is NameArgument nameArg))
{
throw new InvalidArgumentException($"Function name type error: Type = {name.GetType().Name}, Value = {name.ToString()}");
}
if (!funcs.TryGetValue(nameArg.Value, out var func))
{
throw new InvalidArgumentException($"Function does not exist: \"{nameArg.Value}\"");
}
// Get next character:
if (!source.SkipWhiteSpace(ref chr))
{
throw new FinalCharacterException("Expected closing ')'");
}
var funcArg = new FunctionArgument()
{
Call = new FunctionCall(0) // Line number doesn't really matter, as this isn't a whole statement
{
Function = func
}
};
if (chr == ':')
{
// Arguments to go with it
if (!source.AdvanceWhiteSpace(out chr))
{
throw new FinalCharacterException("Expected argument list");
}
funcArg.Call.Arguments = Arguments.Multiple(source, ref chr, funcs);
// Get closing bracket
if (!source.SkipWhiteSpace(ref chr))
{
throw new FinalCharacterException("Expected closing ')'");
}
else if (chr != ')')
{
throw new InvalidCharacterException($"Expected closing ')': found '{chr}'");
}
}
else if (chr != ')')
{
throw new InvalidCharacterException($"Expected closing ')' or arguments (':'): found '{chr}'");
}
source.Advance(out chr);
return(funcArg);
}
public static IArgument Number(CharSource source, ref char chr)
{
var integral = source.ReadInt(ref chr);
if (chr == '.')
{
if (!source.Advance(out chr))
{
throw new FinalCharacterException("Expected fractional value after '.'");
}
else if (!char.IsDigit(chr))
{
throw new InvalidCharacterException($"Expected fractional value after '.': found '{chr}'");
}
var fractional = source.ReadFractional(ref chr);
var mantissa = integral >= 0 ? integral + fractional : integral - fractional;
if (char.ToLower(chr) == 'e')
{
if (!source.AdvanceWhiteSpace(out chr))
{
throw new FinalCharacterException("Expected exponent after 'e'");
}
else if (!CharSource.IsNumberStart(chr))
{
throw new InvalidCharacterException($"Expected exponent after 'e': found '{chr}'");
}
var exponent = source.ReadInt(ref chr);
mantissa *= Math.Pow(10, exponent);
}
return(new DoubleLiteral()
{
Value = mantissa
});
}
return(new IntegerLiteral()
{
Value = integral
});
}
public static IArgument Executable(CharSource source, ref char chr, Dictionary <string, IFunction> funcs)
{
// Having seen '<'
if (!source.AdvanceWhiteSpace(out chr))
{
throw new FinalCharacterException("Expected statements, or closing '>'");
}
var exec = new ExecutableArgument();
// Statement reading takes us to the first character of the next potential
while (true)
{
if (chr == '>')
{
source.Advance(out chr);
return(exec);
}
var statement = Statement(source, ref chr, funcs);
exec.Value.Add(statement);
}
}
public static ArgumentList Multiple(CharSource source, ref char chr, Dictionary <string, IFunction> funcs)
{
var args = new ArgumentList();
// Typically get here having seen nothing or the first character already
// Running out of text here is not an error, unless specified as more to come
while (source.SkipWhiteSpace(ref chr))
{
var arg = Single(source, ref chr, funcs);
args.Add(arg);
if (!source.SkipWhiteSpace(ref chr))
{
return(args);
}
else if (chr != ',')
{
return(args);
}
source.Advance(out chr);
}
// No need to throw here, as if more expected single argument parsing will catch
return(args);
}