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Postings from November 2003
On Wed, Nov 19, 2003 at 09:30:15AM -0700, Luke Palmer wrote:
: Piers Cawley writes:
: > All of which means you can wrap it up in a macro and prove Simon's
: > point about what's syntax and what's CP6AN:
: >
: > macro unless_all( Block &test is parsed /<perl.expression>/,
: > Block &consequence, *@ary )
: > { my $guard = Object.new;
: > for *@ary, $guard
: > -> { when $guard { &consequence() ; last }
: > when &test { last } } }
: >
: > But I've probably got the signature slightly wrong.
So far we've only allowed "is parsed" on the macro itself, not on
individual arguments. Still, that's an interesting idea.
: I think the only thing that's wrong with your signature is that you said
: "macro" instead of "sub". Well, and &test has to be finessed into an
: executable block somehow, but we're not supposed to know how yet.
Hmm, how about statement:unless_all and modifier:unless_all?
: > Higher Order Functions/Methods/Macros are great aren't they?
:
: What a modern thinker! Use a *function* to do a common task? *What*
: are you talking about!? :-)
Well, you mayn't put "is parsed" on a function. Macros have special
rules to enforce lexical scoping of syntax munging, since the syntax
must be known when the call is parsed. A function call can be parsed
without such special knowledge.
Larry
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