5 ms·

(mapdo .start-time.(set 42) obj-list) (swap [a 2..4] [b 0..2]) This looks gross. Why does no one seem to understand that lisp should not have infix operators

• deleted 3y ago
  [deleted]
• kazinator 3y ago
  I respect the idea that Lisp syntax should only be based on dispatch based on looking at the leftmost input character. In TXR Lisp, I decided to experiment with a small number of notations, to see whether they could make Lisp coding a bit more ergonomic, similarly to how 'x has helped with (quote x) for over sixty years. There are rules: the notations have to absolutely fit into the surrounding Lisp. The notations all have an underlying equivalent tree structure: list headed by a specific symbol. There must be print-read consistency. Not all combinations of the underlying structure need to (or should) map to the notation. 1> '(qref a b c d) a.b.c.d 2> '(qref a b (qref c d)) (qref a b c.d) 3> '(qref (qref a b) (qref c d)) (qref a.b c.d) 4> '(qref 1 0) (qref 1 0) 5> '(qref 1 a) (qref 1 a) 6> '(qref a 1) (qref a 1) Not every (qref X Y) is blindly printed as X.Y, which would break print-read consistency. Multiple different qref nestings would map to the same notation, and (qref 1 0) would produce the floating-point token 1.0. Of course, some of these notations complicate parsing. When we see a symbol token like a, we cannot just return the symbol, because it could be followed by a dot, in which case we are in (qref a ... syntax, or other possibilities. Be that as it may, working with this stuff is fine; all in a day's Lisp.