NAME

No::Worries::Warn - warning handling without worries

SYNOPSIS

  use No::Worries::Warn qw(warnf handler);
  if (open($fh, "<", $path)) {
      ... so something in case of success ...
  } else {
      warnf("cannot open(%s): %s", $path, $!);
      ... do something else in case of failure ...
  }
  $ ./myprog
  myprog: cannot open(foo): No such file or directory
  $ NO_WORRIES=cluck ./myprog
  myprog: cannot open(foo): No such file or directory at myprog line 16
      main::test() called at ./myprog line 19

DESCRIPTION

This module eases warning handling by providing a convenient wrapper around warn() with sprintf()-like API. warnf() is to warn() what printf() is to print() with, in addition, the trimming of leading and trailing spaces.

It also provides a handler for warn() that prepends a prefix ($No::Worries::Warn::Prefix) to all warnings. It also uses the "NO_WORRIES" environment variable to find out if Carp's carp() or cluck() should be used instead of warn(). Finally, the wrapper can be told to also log warnings to syslog (see $No::Worries::Warn::Syslog).

This handler can be installed simply by importing it:

  use No::Worries::Warn qw(warnf handler);

Alternatively, it can be installed "manually":

  use No::Worries::Warn qw(warnf);
  $SIG{__WARN__} = \&No::Worries::Warn::handler;

FUNCTIONS

This module provides the following functions (none of them being exported by default):

warnf(MESSAGE)

report a warning described by the given MESSAGE

warnf(FORMAT, ARGUMENTS...)

idem but with sprintf()-like API

handler(MESSAGE)

$SIG{__WARN__} compatible warning handler (this function cannot be imported)

GLOBAL VARIABLES

This module uses the following global variables (none of them being exported):

$Prefix

prefix to prepend to all warnings (default: the program name)

$Syslog

true if warnings should also be sent to syslog using No::Worries::Syslog's syslog_warning() (default: false)

ENVIRONMENT VARIABLES

This module uses the "NO_WORRIES" environment variable to control how warnings should be reported. Supported values are:

"carp"

Carp's carp() will be used instead of warn()

"cluck"

Carp's cluck() will be used instead of warn()

SEE ALSO

Carp, No::Worries, No::Worries::Die, No::Worries::Syslog.

AUTHOR

Lionel Cons <http://cern.ch/lionel.cons>

Copyright (C) CERN 2012-2019