Re^2: ** operator in perl

in reply to Re: ** operator in perl
in thread ** operator in perl

I was puzzled by this one too ...

[me@ptmr]/home/me$ perl -le 'print   -2  ** 4 ' # ** binds before -
-16
[me@ptmr]/home/me$ perl -le 'print  (-2) ** 4 ' # this puzzled me
-2
[me@ptmr]/home/me$ perl -le 'print ((-2) ** 4)' # parenthesis force wh
+at I want
16
[download]

but I guess print is handling the second case as a list followed by some irrelevance, do I have that about right ?

Update: Thanks Fletch now I have been enlightened! I last read perlfunc a long time ago and had not really absorbed it all at the time. Now I see the explanation print (something) something_else gives the warning print (...) interpreted as function because it looks like a function.

Cheers,
R.

Pereant, qui ante nos nostra dixerunt!

Comment on Re^2: ** operator in perl Select or Download Code

Replies are listed 'Best First'.
Re^3: ** operator in perl by Fletch (Bishop) on Feb 03, 2009 at 13:16 UTC
print is a list operator, so the second parses as `(print(-2))4` and will produce a warning if you run with `-w`/warnings (`Useless use of exponentiation () in void context at -e line 1.`). Update: I mean it's not like perlfunc uses `print` as the example of precedence issues that can come up with list operators right in the second paragraph or anything . . . The cake is a lie. The cake is a lie. The cake is a lie.	[reply] [d/l] [select]

Replies are listed 'Best First'.

Re^3: ** operator in perl
by Fletch (Bishop) on Feb 03, 2009 at 13:16 UTC

print is a list operator, so the second parses as (print(-2))**4 and will produce a warning if you run with -w/warnings (Useless use of exponentiation (**) in void context at -e line 1.).

Update: I mean it's not like perlfunc uses print as the example of precedence issues that can come up with list operators right in the second paragraph or anything . . .

The cake is a lie.
The cake is a lie.
The cake is a lie.

[reply]
[d/l]
[select]

In Section Seekers of Perl Wisdom