diff options
author | Gurusamy Sarathy <gsar@cpan.org> | 1999-05-24 07:24:11 +0000 |
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committer | Gurusamy Sarathy <gsar@cpan.org> | 1999-05-24 07:24:11 +0000 |
commit | 19799a22062ef658e4ac543ea06fa9193323512a (patch) | |
tree | ae9ae04d1351eb1dbbc2ea3cfe207cf056e56371 /pod/perlsyn.pod | |
parent | d92eb7b0e84a41728b3fbb642691f159dbe28882 (diff) | |
download | perl-19799a22062ef658e4ac543ea06fa9193323512a.tar.gz |
major pod update from Tom Christiansen
p4raw-id: //depot/perl@3460
Diffstat (limited to 'pod/perlsyn.pod')
-rw-r--r-- | pod/perlsyn.pod | 20 |
1 files changed, 9 insertions, 11 deletions
diff --git a/pod/perlsyn.pod b/pod/perlsyn.pod index a3bc5ab547..ee668e1187 100644 --- a/pod/perlsyn.pod +++ b/pod/perlsyn.pod @@ -44,7 +44,7 @@ subroutine without defining it by saying C<sub name>, thus: sub myname; $me = myname $0 or die "can't get myname"; -Note that it functions as a list operator, not as a unary operator; so +Note that my() functions as a list operator, not as a unary operator; so be careful to use C<or> instead of C<||> in this case. However, if you were to declare the subroutine as C<sub myname ($)>, then C<myname> would function as a unary operator, so either C<or> or @@ -86,7 +86,7 @@ presuming you're a speaker of English. The C<foreach> modifier is an iterator: For each value in EXPR, it aliases C<$_> to the value and executes the statement. The C<while> and C<until> modifiers have the usual "C<while> loop" semantics (conditional evaluated first), except -when applied to a C<do>-BLOCK (or to the now-deprecated C<do>-SUBROUTINE +when applied to a C<do>-BLOCK (or to the deprecated C<do>-SUBROUTINE statement), in which case the block executes once before the conditional is evaluated. This is so that you can write loops like: @@ -289,9 +289,7 @@ is therefore visible only within the loop. Otherwise, the variable is implicitly local to the loop and regains its former value upon exiting the loop. If the variable was previously declared with C<my>, it uses that variable instead of the global one, but it's still localized to -the loop. (Note that a lexically scoped variable can cause problems -if you have subroutine or format declarations within the loop which -refer to it.) +the loop. The C<foreach> keyword is actually a synonym for the C<for> keyword, so you can use C<foreach> for readability or C<for> for brevity. (Or because @@ -490,15 +488,15 @@ C<HTTP_USER_AGENT> envariable. That kind of switch statement only works when you know the C<&&> clauses will be true. If you don't, the previous C<?:> example should be used. -You might also consider writing a hash instead of synthesizing a C<switch> -statement. +You might also consider writing a hash of subroutine references +instead of synthesizing a C<switch> statement. =head2 Goto -Although not for the faint of heart, Perl does support a C<goto> statement. -A loop's LABEL is not actually a valid target for a C<goto>; -it's just the name of the loop. There are three forms: C<goto>-LABEL, -C<goto>-EXPR, and C<goto>-&NAME. +Although not for the faint of heart, Perl does support a C<goto> +statement. There are three forms: C<goto>-LABEL, C<goto>-EXPR, and +C<goto>-&NAME. A loop's LABEL is not actually a valid target for +a C<goto>; it's just the name of the loop. The C<goto>-LABEL form finds the statement labeled with LABEL and resumes execution there. It may not be used to go into any construct that |