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0 pointsthrowup2381y ago0 comments

Wouldn’t that match “(foo - bar)” as well as “(foo-bar)”? I don’t think you can get around token whitespace in macro_rules

0 comments

quasigloam1y ago

Yes it would match both, this would require us to assume that "foo - bar" can only be an atom. It's not a great solution.

celeritascelery1y ago

It would, but lisp has prefix operators, so you wouldn’t have to worry about it getting confused.

quasigloam1y ago

Although in a Lisp such as Scheme, you could pass around the negation operator in something like (map - '(1 2 3)), so it would be a valid concern that it might clash.

tmtvl1y ago

The problem with that is that there are spaces between map, -, and '(1 2 3). The only way to get spaces into a name is by using vertical bars:

  (defvar |do i 10| 1.100)

j / k navigate · click thread line to collapse

0 comments

quasigloam1y ago

Yes it would match both, this would require us to assume that "foo - bar" can only be an atom. It's not a great solution.

celeritascelery1y ago

It would, but lisp has prefix operators, so you wouldn’t have to worry about it getting confused.

quasigloam1y ago

Although in a Lisp such as Scheme, you could pass around the negation operator in something like (map - '(1 2 3)), so it would be a valid concern that it might clash.

tmtvl1y ago

The problem with that is that there are spaces between map, -, and '(1 2 3). The only way to get spaces into a name is by using vertical bars:

  (defvar |do i 10| 1.100)

j / k navigate · click thread line to collapse