Hi all
My question is related to following sample code which tries to change consant value by pointers.(I know it is wrong practice but i am surprised by mis-behaviour)
The code:
#include <stdio.h>
int main()
{
const int x = 10;
int *y;
const int * const z = &x;
y = (int *)&x;... (2 Replies)
I used the eval command in shell programming for assigning a value to a stored value of a variable.
Example:
VAR="Unix_Id"
eval $VAR="101"
eval echo $"$VAR"
How can i assign a value to a stored value of a variable in perl OR how i can write above code in Perl?
I need your help... (4 Replies)
Hello there,
I'd like to define a variable b equal to 0.5/a where a=0.001, so I wrote something like that:
a=0.001;
let 'b=0.5/$a';
but it doesn't work... maybe because the variable a has a real value???
Any help will be appreciated!!!:D (1 Reply)
Hi all,
some small script with eval turned me to crazy.
my OS is linux
Linux s10-1310 2.6.16.53-0.8.PTF.434477.3.TDC.0-smp #1 SMP Fri Aug 31 06:07:27 PDT 2007 x86_64 x86_64 x86_64 GNU/Linux
below script works well
#!/bin/bash
eval ssh remotehost date
eval ssh remotehost ls
below... (1 Reply)
Hi All,
I read the above written code (perl code) in another perl script and evaluates this code for each line of text file,but using exit statement in code make this not to work and i could not get the desired results. However if i use return it works fine. I just need to know why it doesn't... (1 Reply)
Hello All,
I am trying to use perl eval in a complex code and below given is a pseudo code of my logic.
Here $result evalutes to empty.
Please help.How should I retrieve of $t where $f just hold the name of varaible i.e t
$t=10;
$f='$t';
$result=eval "\$$f";
print "$result\n"; (3 Replies)
Perl::Critic::Policy::BuiltinFunctions::ProhibitStringyEUser3Contributed Perl DocumePerl::Critic::Policy::BuiltinFunctions::ProhibitStringyEval(3)NAME
Perl::Critic::Policy::BuiltinFunctions::ProhibitStringyEval - Write "eval { my $foo; bar($foo) }" instead of "eval "my $foo; bar($foo);"".
AFFILIATION
This Policy is part of the core Perl::Critic distribution.
DESCRIPTION
The string form of "eval" is recompiled every time it is executed, whereas the block form is only compiled once. Also, the string form
doesn't give compile-time warnings.
eval "print $foo"; # not ok
eval {print $foo}; # ok
CONFIGURATION
There is an "allow_includes" boolean option for this Policy. If set, then strings that look like they only include a single "use" or
"require" statement (with the possible following statement that consists of a single number) are allowed. With this option set, the
following are flagged as indicated:
eval 'use Foo'; # ok
eval 'require Foo'; # ok
eval "use $thingy;"; # ok
eval "require $thingy;"; # ok
eval "use $thingy; 1;"; # ok
eval "require $thingy; 1;"; # ok
eval 'use Foo; blah;'; # still not ok
eval 'require Foo; 2; 1;'; # still not ok
eval 'use $thingy;'; # still not ok
eval 'no Foo'; # still not ok
If you don't understand why the number is allowed, see Perl::Critic::Policy::ErrorHandling::RequireCheckingReturnValueOfEval.
This option inspired by Ricardo SIGNES' Perl::Critic::Policy::Lax::ProhibitStringyEval::ExceptForRequire.
SEE ALSO
Perl::Critic::Policy::ControlStrucutres::RequireBlockGrep
Perl::Critic::Policy::ControlStrucutres::RequireBlockMap
AUTHOR
Jeffrey Ryan Thalhammer <jeff@imaginative-software.com>
COPYRIGHT
Copyright (c) 2005-2011 Imaginative Software Systems. All rights reserved.
This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. The full text of this license
can be found in the LICENSE file included with this module.
perl v5.16.3 2014-06-09 Perl::Critic::Policy::BuiltinFunctions::ProhibitStringyEval(3)