man perlop "perlop - Perl operators and precedence" (at least in UNIX-like) answers this question: "Binary "=~" binds a scalar expression to a pattern match." – U. Windl Commented Apr 1, 2020 at 21:11

Apr 5, 2011 · Here the sigil changes to $ to denote that you are accessing a scalar, however the trailing [0] tells perl that it is accessing a scalar element of the array in _ or in other words, @_. – Eric Strom

Dec 30, 2010 · perldoc perlvar is the first place to check for any special-named Perl variable info. Quoting: @_: Within a subroutine the array @_ contains the parameters passed to that subroutine. More details can be found in perldoc perlsub (Perl subroutines) linked from the perlvar: Any arguments passed in show up in the array @_.

Feb 2, 2016 · The => operator in perl is basically the same as comma. The only difference is that if there's an unquoted word on the left, it's treated like a quoted word. The only difference is that if there's an unquoted word on the left, it's treated like a quoted word.

Mar 13, 2015 · So, if the shell is handing you a bunch of file names, and you'd like to go through each one's data in turn, perl's <> operator gives you a nice way of doing that...it puts the next line of the next file (or stdin if no files are named) into $_ (the default scalar). Here is a poor man's grep: while(<>) { print if m/pattern/; } Running this script:

Feb 6, 2011 · Perl arrow operator has one other use: Class−>method invokes subroutine method in package Class. though it's completely different than your code sample. Only including it for completeness for the question in the title.

Nov 10, 2019 · From Perl documentation:. OR List operators. On the right side of a list operator, it has very low precedence, such that it controls all comma-separated expressions found there.

Jun 10, 2011 · However, when I try to google for what each flag means, I mainly get results to generic Perl sites and no specific information regarding the flags or their use is found there. Below are the flags that I encounter most often, and I don't have a clue what they mean: perl -pe; perl -pi; perl -p; perl -w; perl -d; perl -i; perl -t

Learning Perl (豆瓣) 开始。快速浏览加实践下书上代码，两天就可以读个大概。 不过小骆驼书只覆盖了Perl Programming最基础的一部分知识，当你需要用Perl做面对对象或者大型程序编程时，有必要去读一下神兽书—— Intermediate Perl (豆瓣) 。

Sep 3, 2015 · I don't know why the other two suggested disguising && with the lower-precedence and.There's a reason symbols are used to for separators (e.g. ,, ;, { ... }, etc) and it's because it makes it easier to find boundaries in the code at a glance, improving readability.