SE250:lab-9:jsmi233

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I had a go at Option I. I got the equality comparison function down:

bool eqToken( Token a, Token b ) {
	if (a.type != b.type)
		return false;
	switch (a.type) {
		case T_SYMBOL:
		case T_IDENT:
			return a.val.symval == b.val.symval;
		case T_STRING:
			return a.val.strval == b.val.strval;
		case T_INTEGER:
			return a.val.intval == b.val.intval;
		case T_FLOAT:
			return a.val.fltval == b.val.fltval;
	}
	//For all other types, value comparison is not applicable
	return true;
}


The initialize function i guess is supposed to turn a string into a sequence of tokens. I got half way through this, so I'm not sure if I'm on the right track. This is my code:

void init_TokenStream( TokenStream* tokens, char* input ) {
	int pos = 0;
	int start;
	char cur;
	bool dotSeen;

	while (pos < (int)strlen(input)) { 

		if (isalpha(input[pos])) {
			start = pos;
			while (isalpha(input[pos]) || isdigit(input[pos]))
				pos++;
			//We have a string  =D
			
		} else if (isdigit(input[pos])) {
			dotSeen = false;
			start = pos;
			while (true) {
				if (input[pos] == '.') {
					if (dotSeen)
						errorAndDie("Too many dots in numeric expression.");
					else
						dotSeen = true;
				} else if (!isdigit(input[pos]))
					break;
			}
			//We have a number   =D

		} else if (issymbol(input[pos])) {
			//We have a symbol   =D

		} else if (iswhite(input[pos])) {
			//We have whitespace!

		} else if (input[pos]=='"') {
			start = pos;
			pos++;
			while (input[pos] != '"' || (input[pos] == '"' && input[pos - 1] != '\\')
				pos++;
			//We have a string

		}
	}
}