diff options
Diffstat (limited to 'pod')
-rw-r--r-- | pod/perlfunc.pod | 22 | ||||
-rw-r--r-- | pod/perlsub.pod | 2 | ||||
-rw-r--r-- | pod/perltie.pod | 16 |
3 files changed, 20 insertions, 20 deletions
diff --git a/pod/perlfunc.pod b/pod/perlfunc.pod index 00fc8601a4..78a631883e 100644 --- a/pod/perlfunc.pod +++ b/pod/perlfunc.pod @@ -1265,11 +1265,11 @@ there was an error. In the first form, the return value of EXPR is parsed and executed as if it were a little Perl program. The value of the expression (which is itself determined within scalar context) is first parsed, and if there weren't any -errors, executed in the context of the current Perl program, so that any -variable settings or subroutine and format definitions remain afterwards. -Note that the value is parsed every time the eval executes. If EXPR is -omitted, evaluates C<$_>. This form is typically used to delay parsing -and subsequent execution of the text of EXPR until run time. +errors, executed in the lexical context of the current Perl program, so +that any variable settings or subroutine and format definitions remain +afterwards. Note that the value is parsed every time the eval executes. +If EXPR is omitted, evaluates C<$_>. This form is typically used to +delay parsing and subsequent execution of the text of EXPR until run time. In the second form, the code within the BLOCK is parsed only once--at the same time the code surrounding the eval itself was parsed--and executed @@ -2078,9 +2078,9 @@ or equivalently, @foo = grep {!/^#/} @bar; # weed out comments -Note that, because C<$_> is a reference into the list value, it can -be used to modify the elements of the array. While this is useful and -supported, it can cause bizarre results if the LIST is not a named array. +Note that C<$_> is an alias to the list value, so it can be used to +modify the elements of the LIST. While this is useful and supported, +it can cause bizarre results if the elements of LIST are not variables. Similarly, grep returns aliases into the original list, much as a for loop's index variable aliases the list elements. That is, modifying an element of a list returned by grep (for example, in a C<foreach>, C<map> @@ -2462,9 +2462,9 @@ is just a funny way to write $hash{getkey($_)} = $_; } -Note that, because C<$_> is a reference into the list value, it can -be used to modify the elements of the array. While this is useful and -supported, it can cause bizarre results if the LIST is not a named array. +Note that C<$_> is an alias to the list value, so it can be used to +modify the elements of the LIST. While this is useful and supported, +it can cause bizarre results if the elements of LIST are not variables. Using a regular C<foreach> loop for this purpose would be clearer in most cases. See also L</grep> for an array composed of those items of the original list for which the BLOCK or EXPR evaluates to true. diff --git a/pod/perlsub.pod b/pod/perlsub.pod index f45f5494f6..997631674f 100644 --- a/pod/perlsub.pod +++ b/pod/perlsub.pod @@ -39,7 +39,7 @@ To call subroutines: Like many languages, Perl provides for user-defined subroutines. These may be located anywhere in the main program, loaded in from other files via the C<do>, C<require>, or C<use> keywords, or -generated on the fly using C<eval> or anonymous subroutines (closures). +generated on the fly using C<eval> or anonymous subroutines. You can even call a function indirectly using a variable containing its name or a CODE reference. diff --git a/pod/perltie.pod b/pod/perltie.pod index 49bf98999c..b39d7d5336 100644 --- a/pod/perltie.pod +++ b/pod/perltie.pod @@ -310,14 +310,14 @@ the following output demonstrates: =head2 Tying Hashes -As the first Perl data type to be tied (see dbmopen()), hashes have the -most complete and useful tie() implementation. A class implementing a -tied hash should define the following methods: TIEHASH is the constructor. -FETCH and STORE access the key and value pairs. EXISTS reports whether a -key is present in the hash, and DELETE deletes one. CLEAR empties the -hash by deleting all the key and value pairs. FIRSTKEY and NEXTKEY -implement the keys() and each() functions to iterate over all the keys. -And DESTROY is called when the tied variable is garbage collected. +Hashes were the first Perl data type to be tied (see dbmopen()). A class +implementing a tied hash should define the following methods: TIEHASH is +the constructor. FETCH and STORE access the key and value pairs. EXISTS +reports whether a key is present in the hash, and DELETE deletes one. +CLEAR empties the hash by deleting all the key and value pairs. FIRSTKEY +and NEXTKEY implement the keys() and each() functions to iterate over all +the keys. And DESTROY is called when the tied variable is garbage +collected. If this seems like a lot, then feel free to inherit from merely the standard Tie::Hash module for most of your methods, redefining only the |