Hi

is there a way to (temporarily) disable packages?

let's say I wanted to create a DSL for SQL, this partial clause would be legal in Perl

  
sub WHERE(&;$);
WHERE { a IN [1,2,3] or b LIKE '%abc%' };

[download]

and the block would be parsed as indirect method syntax

'IN'->a([1, 2, 3]) or 'LIKE'->b('%abc%');

so I'd need to define packages IN and LIKE to simulate binary operators when executing the BLOCK

  DB<198> {package LIKE; sub AUTOLOAD { my ($field) = $AUTOLOAD =~ m/\
+w+::(\w+)/; print "$field @_" }}
  DB<199> field LIKE '%abc%'

field LIKE %abc%

[download]

so far so good ... but is there a possibility to "disable" the package outside of the block's scope?

The best thing I came up was redefining AUTOLOAD dynamically before and after executing the block to provoke a runtime error

deleting the stash entry for the package in %main:: produced strange problems, probably because of some kind of cashing...

any ideas?

EDIT

at hindsight %INC and @INC might be useful ... (?)

Cheers Rolf
(addicted to the Perl Programming Language and ☆☆☆☆ :)
Je suis Charlie!

In reply to [DSL] disabling packages in Perl? by LanX

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