If global variables $foo, $bar, $buz exist and try to localize them only within a specific scope, I think:
use strict;
use warnings;
use v5.10;
our($foo,$bar,$buz) = qw(foo barbuz);
UPPER_CASE_WORLD: {
# Capitalize global variables for this scope only
no strict 'refs';
local($foo,$bar,$buz) = map {uc${":$_"}}qw(foo barbuz);
say$foo,$bar,$buz;
}
say$foo,$bar,$buz;
1;
When you extend this to "many unspecified global variables", if you use the for loop as it is, you will not be able to produce localized variables outside of for.
#Uppercase many and unspecified global variables
no strict 'refs';
my@globals=qw(foo bar buzz);
local${"::$_"}=uc${"::$_"} for @globals;
# Oh, no, no, no, no, no, no, no, no, no.
say$foo,$bar,$buz;
If you have no choice but to rely on eval, you may need to eat the block itself.I feel a little forced.
use strict;
use warnings;
use v5.10;
our($foo,$bar,$buz) = qw(foo barbuz);
no strict 'refs';
my@globals=qw(foo bar buzz);
my$bunch_of_locals=joinq{},map{
"local\${':$_'}=uc\${':$_'};"
} @globals;
event<<"__UPPER_CASE_WORLD";
{
# Capitalize many and unspecified global variables
$bunch_of_locals
# Do I have to stop here?
say \$foo, \$bar, \$buz;
}
__UPPER_CASE_WORLD
say$foo,$bar,$buz;
1;
If you want to localize many and unspecified global variables at a certain scope, can you write them easily without using eval?
For example, how about the following?
The concept saves the value at the beginning of the scope and returns it to the end (i.e., manual local)
use strict;
use warnings;
use v5.10;
our($foo,$bar,$buz) = qw(foo barbuz);
# sugar-coated syntax function
subusing(&@){
my$code=shift;
my@v=@_;# Save variable contents
$code->(@_);
my$i = 0;
$_=$v[$i++] Restoring the contents of the for@_;# variable
}
using {
$_=uc$_for@_;
say$foo,$bar,$buz;# content changed (global) variable, capitalized.
} $foo, $bar, $buz;# Unspecified variable arguments
say$foo,$bar,$buz;
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