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);
}
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);
}
private static Statement CallArguments(CharSource source, ref char chr, Dictionary <string, IFunction> funcs, IFunction func, int line)
{
// Arrive on ':'
if (!source.AdvanceWhiteSpace(out chr))
{
throw new FinalCharacterException("Expected function arguments");
}
var args = Arguments.Multiple(source, ref chr, funcs);
var fcall = new FunctionCall(line)
{
Function = func,
Arguments = args
};
return(chr == '=' ? Assign(source, ref chr, funcs, fcall, line) : fcall);
}
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);
}
}