add support for ++ and +=

This commit is contained in:
Luna 2019-06-04 18:07:46 -03:00
parent 285f0b8410
commit 498ea72da4

View file

@ -229,6 +229,23 @@ pub const Scanner = struct {
);
}
fn makeTripleMatchToken(
self: *Scanner,
char1: u8,
ttype1: TokenType,
char2,
ttype2: TokenType,
fallback: TokenType,
) Token {
if (self.match(char1)) {
return self.makeToken(ttype1);
} else if (self.match(char2)) {
return self.makeToken(ttype2);
} else {
return self.makeToken(fallback);
}
}
pub fn nextToken(self: *Scanner) !?Token {
self.skipWhitespace();
self.start = self.current;
@ -255,26 +272,14 @@ pub const Scanner = struct {
'$' => self.makeToken(.DollarSign),
'-' => self.makeToken(.Minus),
'+' => self.makeToken(.Plus),
'*' => self.makeToken(.Star),
'%' => self.makeToken(.Modulo),
'!' => self.makeMatchToken('=', .BangEqual, .Bang),
'=' => self.makeMatchToken('=', .EqualEqual, .Equal),
// there can be three tokens from a <
// - <, which is LessThan
// - <=, which is LessEqual
// - <<, which is LeftDoubleChevron
'<' => blk: {
if (self.match('=')) {
break :blk self.makeToken(.LessEqual);
} else if (self.match('<')) {
break :blk self.makeToken(.LeftDoubleChevron);
} else {
break :blk self.makeToken(.Less);
}
},
'>' => self.makeMatchToken('=', .GreaterEqual, .Greater),
'+' => self.makeTripleMatchToken('+', .PlusPlus, '=', .PlusEqual, .Plus),
'<' => self.makeTripleMatchToken('=', .LessEqual, '<', .LeftDoubleChevron, .Less),
'/' => blk: {
var next = self.peekNext();