Aside: Be careful about mixing high and low-precedence logical operators.
----
-class: ex-shellpod
-
-## Document your shell scripts with pod.
-
-```bash
-#!/bin/sh
-
-: <<'=cut'
-=head1 NAME
-
-therapist.sh - This script can save you a bunch of cash
-
-=cut
-
-echo 'Hello. Now, tell me about your problems.'
-
-while read response
-do
- printf "Patient said: %s" "$response" >>therapist_notes.txt
-
- echo 'And how did that make you feel?'
-done
-
-echo "Goodbye! Let's meet again in two weeks."
-```
-
----
-class: ex-shellpod
-
-## Document your shell scripts with pod.
-
-```bash
-#!/bin/sh
-
-: <<'=cut'
-*=head1 NAME
-*
-*therapist.sh - This script can save you a bunch of cash
-*
-*=cut
-
-echo 'Hello. Now, tell me about your problems.'
-
-while read response
-do
- printf "Patient said: %s" "$response" >>therapist_notes.txt
-
- echo 'And how did that make you feel?'
-done
-
-echo "Goodbye! Let's meet again in two weeks."
-```
-
-???
-It's pod! In a shell script.
-
----
-class: ex-shellpod
-
-## Document your shell scripts with pod.
-
-```bash
-#!/bin/sh
-
-*: <<'=cut'
-=head1 NAME
-
-therapist.sh - This script can save you a bunch of cash
-
-=cut
-
-echo 'Hello. Now, tell me about your problems.'
-
-while read response
-do
- printf "Patient said: %s" "$response" >>therapist_notes.txt
-
- echo 'And how did that make you feel?'
-done
-
-echo "Goodbye! Let's meet again in two weeks."
-```
-
-???
-This is the key right here. Anybody know what this is?
-
-It's a heredoc.
-
-The colon command in bourne shell is just noop. Sometimes you'll see the colon used as a type of comment, but unlike
-a comment the shell does parse the arguments to colon.
-
---
class: center, middle
---
class: center, middle
+## Document your shell scripts with pod.
+
+---
+class: ex-shellpod
+
+```bash
+#!/bin/sh
+
+: <<'=cut'
+=head1 NAME
+
+therapist.sh - This script can save you a bunch of cash
+
+=cut
+
+echo 'Hello. Now, tell me about your problems.'
+
+while read response
+do
+ printf "Patient said: %s" "$response" >>therapist_notes.txt
+
+ echo 'And how did that make you feel?'
+done
+
+echo "Goodbye! Let's meet again in two weeks."
+```
+
+---
+class: ex-shellpod
+
+```bash
+#!/bin/sh
+
+: <<'=cut'
+*=head1 NAME
+*
+*therapist.sh - This script can save you a bunch of cash
+*
+*=cut
+
+echo 'Hello. Now, tell me about your problems.'
+
+while read response
+do
+ printf "Patient said: %s" "$response" >>therapist_notes.txt
+
+ echo 'And how did that make you feel?'
+done
+
+echo "Goodbye! Let's meet again in two weeks."
+```
+
+???
+It's pod! In a shell script.
+
+---
+class: ex-shellpod
+
+```bash
+#!/bin/sh
+
+*: <<'=cut'
+=head1 NAME
+
+therapist.sh - This script can save you a bunch of cash
+
+=cut
+
+echo 'Hello. Now, tell me about your problems.'
+
+while read response
+do
+ printf "Patient said: %s" "$response" >>therapist_notes.txt
+
+ echo 'And how did that make you feel?'
+done
+
+echo "Goodbye! Let's meet again in two weeks."
+```
+
+???
+This is the key right here. Anybody know what this is?
+
+It's a heredoc.
+
+The colon command in bourne shell is just noop. Sometimes you'll see the colon used as a type of comment, but unlike
+a comment the shell does parse the arguments to colon.
+
+---
+class: center, middle
+
## Understand calling context.
???
---
class: ex-newfeatures
-## Try some newer perl5 features.
+### Postfix dereferencing
```perl
-*use v5.24;
-*use feature qw(signatures); # available in v5.20
-*no warnings qw(experimental::signatures);
-
-my $missile_inventory = {
- ID => 20,
- WY => 25,
- CA => 195,
-};
+use v5.24;
-*sub get_default_silo_id () {
- return $_ if 0 < $missile_inventory->{$_} for (sort keys $missile_inventory->%*);
- die "No more missiles. :-(\n";
+my $person = {
+ name => 'Bob',
+ associates => [
+ {
+ name => 'Karen',
+ },
+ {
+ name => 'Doug',
+ },
+ ],
}
-*sub launch_missile ( $silo_id = get_default_silo_id() ) {
- die "Silo is empty.\n" if $missile_inventory->{$silo_id} <= 0;
- $missile_inventory->{$silo_id} -= 1;
- say "Missile launched from silo $silo_id.";
-}
+my @others = $person->{associates}->@*;
+my %associate_attributes = $person->{associates}->@[0]->%*;
```
+### `@{...}` can be `->@*` at the end
+### `%{...}` can be `->%*` at the end
+
---
-class: ex-newfeatures
+class: ex-newfeatures2
-## Try some newer perl5 features.
+### Subroutine signatures
```perl
-use v5.24;
-use feature qw(signatures); # available in v5.20
+use v5.20;
+use feature qw(signatures);
no warnings qw(experimental::signatures);
-my $missile_inventory = {
- ID => 20,
- WY => 25,
- CA => 195,
-};
+sub only_one_arg($foo) {
+}
-sub get_default_silo_id () {
-* return $_ if 0 < $missile_inventory->{$_} for (sort keys $missile_inventory->%*);
- die "No more missiles. :-(\n";
+sub other_args_allowed_and_ignored($foo, @) {
}
-sub launch_missile ( $silo_id = get_default_silo_id() ) {
- die "Silo is empty.\n" if $missile_inventory->{$silo_id} <= 0;
- $missile_inventory->{$silo_id} -= 1;
- say "Missile launched from silo $silo_id.";
+sub positional_and_named($args, %other) {
}
+
+# etc.
+```
+
+---
+class: ex-newfeatures2
+
+### Strip leading space in heredocs
+
+```perl
+use v5.26;
+
+do {
+ print <<~'HERE';
+ Hi. The text here is indented in the source code,
+ but not in the console!
+ HERE;
+};
```
---
.col[
- Use [`B::Deparse`](https://metacpan.org/pod/B::Deparse).
-- Document your shell scripts with pod.
- Know regular expressions.
- Use [`Regexp::Debugger`](https://metacpan.org/pod/Regexp::Debugger).
- Write Vim plugins in Perl.
+- Document your shell scripts with pod.
- Understand calling context.
- Understand execution phases.
- Know when to be terse and when not to.
projects / chaz / talk-level-up-your-perl / blobdiff