2 there are two basic syntactic modes:
6 * any letter is an identifier by itself
10 * sequences of letters (and possibly other characters)
11 are collapsed into a single token. Id tokens are separated
12 by any other character not included in one of the collapsing
15 The mode is a property of the parser.
17 there are two basic semantic modes:
21 * implicit operator is multiplication
25 * implicit operator is function application