Lexer in D

[Namespace]

> That would be slower as canFind is linear search.
> Simpler way is use first letter and length to select a bucket 
> of keywords.

I think I get it.
Did you mean something like this?

[code]
immutable ubyte[char] typeMap;
immutable ubyte[char] keywordMap;

static this() {
	typeMap = [
		'd' : 7, 'l' : 16, 'i' : 12, 'u' : 20, 'b' : 0, 'f' : 10, 'r' : 
17, 'v' : 25, 'c' : 2, 's' : 18, 'w' : 26
	];
	
	keywordMap = [
		'_' : 0, 'a' : 6, 'b' : 12, 'c' : 14, 'd' : 20, 'e' : 26, 'f' : 
30, 'g' : 36, 'i' : 37, 'l' : 45,
		'm' : 46, 'n' : 49, 'o' : 52, 'p' : 54, 'r' : 60, 's' : 62, 't' 
: 69, 'u' : 77, 'v' : 79, 'w' : 81
	];
}

bool isKeyword(string value) pure nothrow {
	if (value[0] !in keywordMap) return false;
	
	foreach (string kword; keywords[keywordMap[value[0]] .. $]) {
		if (kword == value) return true;
		if (kword[0] != value[0]) return false;
	}
	
	return false;
}

bool isType(string value) pure nothrow {
	if (value[0] !in typeMap) return false;
	
	foreach (string type; types[typeMap[value[0]] .. $]) {
		if (type == value) return true;
		if (type[0] != value[0]) return false;
	}
	
	return false;
}
[/code]

I'm now by ~230 msecs.