Re^2: What is Perl way to simultaneously assign to three separate arrays?

Thank you for your comments, esp. named captures and proper use of dump.

When I run the code, the array ends up having nine separate scalar elements instead of three references to anonymous arrays containing three scalar elements each

Here's what I'm currently getting:

[
  "/projects/2138137193/iblab?ref=discovery",
  2138137193,
  "iBlab",
  "/projects/2060538158/nz-hosting?ref=discovery",
  2060538158,
  "NZ Hosting",
  "/projects/1956727289/how-to-build-a-spaceship?ref=discovery",
  1956727289,
  "How To Build A Spaceship",
]
[download]

Here's what I want:

[
 [
  "/projects/2138137193/iblab?ref=discovery",
  2138137193,
  "iBlab"
 ],
 [
  "/projects/2060538158/nz-hosting?ref=discovery",
  2060538158,
  "NZ Hosting"
 ],
 [
  "/projects/1956727289/how-to-build-a-spaceship?ref=discovery",
  1956727289,
  "How To Build A Spaceship"
 ]
]
[download]

How is this possible given the constraint that the entire HTML content is a scalar (obtained via LWP)?

(I realize I can "post-process" the @projects array but I'd like to know if everything can be done in a single assignment without any munging afterward.)

#! perl -w

use strict;
use Data::Dump qw(dump);

my $html     =           '<h6 class="project-title"><a href="/projects
+/2138137193/iblab?ref=discovery" target="">iBlab</a></h6><h6 class="p
+roject-title"><a href="/projects/2060538158/nz-hosting?ref=discovery"
+ target="">NZ Hosting</a></h6><h6 class="project-title"><a href="/pro
+jects/1956727289/how-to-build-a-spaceship?ref=discovery" target="">Ho
+w To Build A Spaceship</a></h6>';

my @projects = $html =~ m|<h6 class="project-title"><a href="(/project
+s/(\d+)/.+?\?ref=discovery)" target="">(.+?)</a></h6>|g;

dump \@projects;
[download]

Searched for donut and crumpit. Found donate and stumbit instead.

Comment on Re^2: What is Perl way to simultaneously assign to three separate arrays? Select or Download Code

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Re^3: What is Perl way to simultaneously assign to three separate arrays? by LanX (Saint) on Feb 15, 2015 at 10:42 UTC
> I'd like to know if everything can be done in a single assignment without any munging afterward.) No, you are using /g in list context which swallows the whole file now and returns a flat list. You need an external loop to process the 3 groups update With a post `while` you can have the loop in the same line `push @res, [ $1,$2,$3 ] while m/.../g` In the OP you were originally looping with $_ , that's confusing. you should rather be concerned about maintainability than shortness. Cheers Rolf PS: Je suis Charlie!	[reply] [d/l]
Re^4: What is Perl way to simultaneously assign to three separate arrays? by CoVAX (Beadle) on Feb 15, 2015 at 20:40 UTC
you should rather be concerned about maintainability than shortness. Agreed. Still, I am fascinated by idiomatic Perl and its myriad other ways of doing something (the Schwartzian Transform comes to mind). Searched for donut and crumpit. Found donate and stumbit instead.	[reply]
Re^3: What is Perl way to simultaneously assign to three separate arrays? by CoVAX (Beadle) on Feb 15, 2015 at 08:42 UTC
Here's what I came up with to "post-process" the array to get what I wanted: #! /usr/bin/perl -w use strict; use Data::Dump qw(dump); my @src = ( "/projects/2138137193/iblab?ref=discovery", 2138137193, "iBlab", "/projects/2060538158/nz-hosting?ref=discovery", 2060538158, "NZ Hosting", "/projects/1956727289/how-to-build-a-spaceship?ref=discovery", 1956727289, "How To Build A Spaceship" ); my @dst = (); my $by = 3; my $len = @src / $by; die "Not an integral multiple\n" unless ( 0 == @src % $by ); for (my $i = 0; $i < $len; $i++) { push @dst, [ splice @src, 0, 3 ]; } dump \@dst; [download] The output: `[ [ "/projects/2138137193/iblab?ref=discovery", 2138137193, "iBlab", ], [ "/projects/2060538158/nz-hosting?ref=discovery", 2060538158, "NZ Hosting", ], [ "/projects/1956727289/how-to-build-a-spaceship?ref=discovery", 1956727289, "How To Build A Spaceship", ], ]` [download] I don't know why but lately I've been in a mood to "do it in one statement" or "do it in place". So I have to ask: "Can this be done in-place with just one array?" Searched for donut and crumpit. Found donate and stumbit instead.	[reply] [d/l] [select]


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Re^2: What is Perl way to simultaneously assign to three separate arrays?

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