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 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);
}
public static Executable Parse(CharSource source, Dictionary <string, IFunction> funcs)
{
// Get to first character
var exec = new Executable();
if (!source.Advance(out var chr))
{
return(exec);
}
// Always ends on first character of next statement, if possible
while (source.SkipWhiteSpace(ref chr))
{
var statement = Statement(source, ref chr, funcs);
exec.Add(statement);
}
return(exec);
}
