Assuming the following code
sub foo {
dosomething {...}
else { foo }
is the number of times foo has been called kept track of internally and how could I access that count? (1 Reply)
Hello people,
Need help !!! What am I doing wrong here ?
I am writing a function to recursively list the files under a folder and it's sub-folders. Problem is once it list the files under the innermost folder, it terminates. What do I need to do so that it returns and list files under the... (3 Replies)
Hi, Can anyone help me figure out the problem I'm having with a function call?
I have a header file, which sets an enum:
typedef enum {INFO, WARNING, FATAL} Levels;
int log_event (Levels, char *fmt, ...);
..then the function is called this way:
log_event(INFO, "Message text");
... (6 Replies)
I have a function check_ok in my abc.sh. which return me 1 or 0 . I want to call this fuction through other shell script. this shell also send two parameter to calling function.
Can you please tell me how. I am very new in unix.
#!/bin/bash
date_equal()
{
sqlplus -silent... (4 Replies)
hi,
can any one help me to correct this function call.
awk -F "," '{ {first=$1; sec=$2; tro=$3;quat=$4 }
if (tro == "")
{
$3 = search "$file2" "$first" "$file3"
{print $1","$2","$3","$4} }
else
{print $1","$2","$3 $4}}' $file1 > $file
search ()
{ (2 Replies)
Hi foiks
i am unable to find what is wrong in my code
mu functionality is to exit from shell when i give 99 but it is not calling function ext
Could you please correct me.
read option
if ;
then
ext
else
echo "out"
fi
function ext
{
echo "tested 99 and exit... (12 Replies)
Hi,
I am running a perl script to automate a process and I keep running into a error can't find the "value"
Can't call method "value" on an undefined value at process_file.pl line 44.
file is CVS
cell is ifdfdxrfmp.ksh
Here is the script I have also attached it as well:
... (2 Replies)
Hi
I have created a function in a Shell Script test.sh
function fnTest()
{
echo "My first Method
}
I have called this function in my test.sh
cat abc.txt | grep "test"
echo " test"
fnTest
But while running the shell script i got the following error:
... (2 Replies)
Discussion started by: nanthagopal
2 Replies
LEARN ABOUT MOJAVE
context::preserve5.18
Context::Preserve(3) User Contributed Perl Documentation Context::Preserve(3)NAME
Context::Preserve - run code after a subroutine call, preserving the context the subroutine would have seen if it were the last statement
in the caller
SYNOPSIS
Have you ever written this?
my ($result, @result);
# run a sub in the correct context
if(!defined wantarray){
some::code();
}
elsif(wantarray){
@result = some::code();
}
else {
$result = some::code();
}
# do something after some::code
$_ += 42 for (@result, $result);
# finally return the correct value
if(!defined wantarray){
return;
}
elsif(wantarray){
return @result;
}
else {
return $result;
}
Now you can just write this instead:
use Context::Preserve;
return preserve_context { some::code() }
after => sub { $_ += 42 for @_ };
DESCRIPTION
Sometimes you need to call a function, get the results, act on the results, then return the result of the function. This is painful
because of contexts; the original function can behave different if it's called in void, scalar, or list context. You can ignore the
various cases and just pick one, but that's fragile. To do things right, you need to see which case you're being called in, and then call
the function in that context. This results in 3 code paths, which is a pain to type in (and maintain).
This module automates the process. You provide a coderef that is the "original function", and another coderef to run after the original
runs. You can modify the return value (aliased to @_) here, and do whatever else you need to do. "wantarray" is correct inside both
coderefs; in "after", though, the return value is ignored and the value "wantarray" returns is related to the context that the original
function was called in.
EXPORT
"preserve_context"
FUNCTIONS
preserve_context { original } [after|replace] => sub { after }
Invokes "original" in the same context as "preserve_context" was called in, save the results, runs "after" in the same context, then
returns the result of "original" (or "after" if "replace" is used).
If the second argument is "after", then you can modify @_ to affect the return value. "after"'s return value is ignored.
If the second argument is "replace", then modifying @_ doesn't do anything. The return value of "after" is returned from
"preserve_context" instead.
Run "preserve_context" like this:
sub whatever {
...
return preserve_context { orginal_function() }
after => sub { modify @_ };
}
or
sub whatever {
...
return preserve_context { orginal_function() }
replace => sub { return @new_return };
}
Note that there's no comma between the first block and the "after =>" part. This is how perl parses functions with the "(&@)" prototype.
The alternative is to say:
preserve_context(sub { original }, after => sub { after });
You can pick the one you like, but I think the first version is much prettier.
AUTHOR AND COPYRIGHT
Jonathan Rockway "<jrockway@cpan.org>"
Copyright (c) 2008 Infinity Interactive. You may redistribute this module under the same terms as Perl itself.
perl v5.18.2 2008-01-15 Context::Preserve(3)