Saturday, February 27, 2010

Generalizing Javadot

The idea of Javadot is to allow the rich lexical syntax of Lisp and Scheme with the elegance of the dot-notation from the C tradition by simply allowing scope to trump lexical splitting: if is in scope as an identifier, then it parses as a variable reference; otherwise it parses as "foo" "." "bar". It's a simple compromise, it's easy to understand, it plays well with lexical scope, and (in an infix language) you can always circumvent it with whitespace. (I don't think it needs to complicate parsing too much, either, since you can do a post-hoc splitting of the lexeme, rather than forcing the lexer to understand scope the way you're forced to with the C typedef ambiguity).

My question is: couldn't you use this idea in an infix language, and generalize it to work for all infix operators? This would allow the use of other common operators such as -, +, *, /, <, and >, all of which I've loved being able to use in identifier names in Scheme, and all of which I also really like being able to use as infix operators.

Friday, February 12, 2010

Eich's Law

Found this gem in a C++ comment while digging in the SpiderMonkey codebase:
After much testing, it's clear that Postel's advice to protocol designers ("be liberal in what you accept, and conservative in what you send") invites a natural-law repercussion for JS as "protocol":

"If you are liberal in what you accept, others will utterly fail to be conservative in what they send."
The comment is unsigned, but it sounds like Brendan.