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use less in perl6?

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From:
Yuval Kogman
Date:
March 30, 2005 00:20
Subject:
use less in perl6?
Message ID:
20050330082028.GA2303@woobling.org
Perl 6 has some more interesting capabilities for lexical scoped
hinting of tradeoff preferences. For example:

	use less precision; # the default nums created in this scope are
	# lower precision floats

	use less cpu; # many places this can have a desired effect
	use less memory; # especially in the underlying impls of
	# structures

	use less stuff; # might have a meaning for a library

Mostly I think it's a matter of just controlling the default parrot
PMC implementations underlying the structures. Aside from that there
might be some other, perhaps more global settings.

IMHO perl6 should allow some control over these. Here's where the
design comes in:

	control over lexical scoped params, vs. application wide ones

	granuality of control and it's coupling to parrot

	control from the perspective of the user of a library - who is
	responsible? how is that expressed? is it per context? per
	object? per scope? globally scoped?

	how is it future proofed? i'd like to tell a piddle impl i want
	some behavior, and I'd like my program to exploit it if i
	subsequently update the piddle implementation, and it suddenly
	learns what i mean.

How should this stuff be expressed? 'use less' is cute, but i don't
think it really gets there.

Perhaps this interface, or it's principals should also allow
similarly controlled debugging/tracing. Usually when trying to look
inside a big app, you are only concerned about a specific part. I
think this is very analogeous to optimization hints:

	sometimes you want to override it form the command line

	sometimes you only want it to apply to calls from a certain
	place

	sometimes you want to enable it from within the code it applies
	to, and sometimes outside of it

	you often want a volume knob for this behavior

	you want several instances of usage to not conflict

I'd like to see what the design team can do about this.

Ciao!

-- 
 ()  Yuval Kogman <nothingmuch@woobling.org> 0xEBD27418  perl hacker &
 /\  kung foo master: /me groks YAML like the grasshopper: neeyah!!!!!!


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