1. Enable warnings from command line: perl -w
2. Through Shebang line: #!/usr/bin/perl -w
However this doesn't work in case of #!/usr/bin/env perl -w because env tries to treat "perl -w" as single argument.
3. use warnings - However this has lexical implications and only applies to current code
4. BEGIN{
$^W = 1
}
BEGIN block is executed during compilation and hence this sets warnings switch to true and applies to all the scripts that get executed/imported during this execution.
2. Through Shebang line: #!/usr/bin/perl -w
However this doesn't work in case of #!/usr/bin/env perl -w because env tries to treat "perl -w" as single argument.
3. use warnings - However this has lexical implications and only applies to current code
4. BEGIN{
$^W = 1
}
BEGIN block is executed during compilation and hence this sets warnings switch to true and applies to all the scripts that get executed/imported during this execution.
