Eily asked in the CB, here the answer: *
Basically:
- each has no problem if you delete the current element
- if you delete other elements, you need to reset the iterator, e.g. with keys
- then the iterator starts anew with the remaining elements
- NB if you don't empty the whole hash, you risk an endless loop.
The following demo is always resetting, but doesn't need to.
DB<41> @h{a..c,A..C} = (1..3,11..13)
DB<42> x \%h
0 HASH(0x33bf940)
'A' => 11
'B' => 12
'C' => 13
'a' => 1
'b' => 2
'c' => 3
DB<43> while (my ($k,$v) = each %h ) { delete $h{$k}; print "$k,$v\n
+"; delete $h{uc($k)} } continue {keys %h }
c,3
a,1
B,12
b,2
Question to follow ;-P
UPDATE
*) this was a root post which was re-parented to the later question. Partly because it toook eily more than 15 min to ask, but mainly because I liked the idea to defy causality! ;-)
-
Are you posting in the right place? Check out Where do I post X? to know for sure.
-
Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:
<code> <a> <b> <big>
<blockquote> <br /> <dd>
<dl> <dt> <em> <font>
<h1> <h2> <h3> <h4>
<h5> <h6> <hr /> <i>
<li> <nbsp> <ol> <p>
<small> <strike> <strong>
<sub> <sup> <table>
<td> <th> <tr> <tt>
<u> <ul>
-
Snippets of code should be wrapped in
<code> tags not
<pre> tags. In fact, <pre>
tags should generally be avoided. If they must
be used, extreme care should be
taken to ensure that their contents do not
have long lines (<70 chars), in order to prevent
horizontal scrolling (and possible janitor
intervention).
-
Want more info? How to link
or How to display code and escape characters
are good places to start.
|