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authorEgor Tensin <Egor.Tensin@gmail.com>2022-04-05 11:38:44 +0200
committerEgor Tensin <Egor.Tensin@gmail.com>2022-04-05 11:38:44 +0200
commitb3211b8aa24a3b03d2a39b49f255d4cdc1cd40df (patch)
treeb8de4ce1b20ea6553afc114f246cf3a197a6b0cb /_notes
parentnotes/bash: redesign (diff)
downloadblog-b3211b8aa24a3b03d2a39b49f255d4cdc1cd40df.tar.gz
blog-b3211b8aa24a3b03d2a39b49f255d4cdc1cd40df.zip
notes/bash: generate HTML programmatically
Diffstat (limited to '_notes')
-rw-r--r--_notes/bash.html146
-rw-r--r--_notes/bash.md208
2 files changed, 146 insertions, 208 deletions
diff --git a/_notes/bash.html b/_notes/bash.html
new file mode 100644
index 0000000..ea0cb8a
--- /dev/null
+++ b/_notes/bash.html
@@ -0,0 +1,146 @@
+---
+title: Bash
+subtitle: best practices
+layout: plain
+features:
+ - title: Arrays
+ topics:
+ - title: Declaration
+ do:
+ - |
+ local -a xs=()
+ declare -a xs=()
+ local -A xs=()
+ declare -A xs=()
+
+ # Works with nounset:
+ echo "${#xs[@]}"
+ dont:
+ - |
+ local -a xs
+ declare -a xs
+ local -A xs
+ declare -A xs
+
+ # Doesn't work with nounset:
+ echo "${#xs[@]}"
+ - title: Expansion
+ do:
+ - |
+ func ${arr[@]+"${arr[@]}"}
+ dont:
+ - |
+ # Doesn't work with nounset:
+ func "${arr[@]}"
+ # Doesn't work properly with `declare -a arr=('')`:
+ func "${arr[@]+"${arr[@]}"}"
+ - title: unset
+ do:
+ - |
+ unset -v 'arr[x]'
+ unset -v 'arr[$i]'
+ dont:
+ - |
+ # May break due to globbing:
+ unset -v arr[x]
+ # In addition, possible quoting problem:
+ unset -v arr[$i]
+ # Doesn't work for some reason:
+ unset -v 'arr["x"]'
+ unset -v 'arr["]"]'
+ # Also rejected:
+ unset -v 'arr["$i"]'
+
+ # An insightful discussion on the topic:
+ # https://lists.gnu.org/archive/html/help-bash/2016-09/msg00020.html
+ - title: errexit
+ topics:
+ - title: Command substitution
+ do:
+ - |
+ # Without this, bar will be executed w/ errexit disabled!
+ shopt -s inherit_errexit
+
+ bar() {
+ false
+ echo 'should never see this' >&2
+ }
+
+ bar_output="$( bar )"
+ foo "$bar_output"
+ dont:
+ - |
+ bar() {
+ false
+ echo 'should never see this' >&2
+ }
+
+ # Even with errexit, foo will still get executed.
+ # More than that, the script will print 'should never see this'!
+ foo "$( bar )"
+ - title: Process substitution
+ do:
+ - |
+ shopt -s lastpipe
+
+ command | while IFS= read -r line; do
+ process_line "$line"
+ done
+ dont:
+ - |
+ # Without lastpipe, you cannot pipe into read:
+ command | while IFS= read -r line; do
+ process_line "$line"
+ done
+ - |
+ # errexit doesn't work here no matter what:
+ while IFS= read -r line; do
+ process_line "$line"
+ done < <( command )
+ echo 'should never see this'
+ - |
+ # This would break if $output contains the \0 byte:
+ output="$( command )"
+
+ while IFS= read -r line; do
+ process_line "$line"
+ done <<< "$output"
+ - title: Functions
+ do:
+ - |
+ foo() {
+ false
+ echo 'should never see this' >&2
+ }
+
+ foo
+ echo ok
+ dont:
+ - |
+ # foo will still print 'should never see this'.
+ if foo; then
+ echo ok
+ fi
+
+ # Same below.
+ foo && echo ok
+ foo || echo ok
+---
+{% for feature in page.features %}
+ <h2>{{ feature.title }}</h2>
+ {% for topic in feature.topics %}
+ <h3>{{ topic.title }}</h3>
+ <div class="row">
+ <div class="col-md-6">
+ {% for guide in topic.do %}
+ {% highlight bash %}{{ guide }}{% endhighlight %}
+ {% endfor %}
+ </div>
+ <div class="col-md-6">
+ {% for guide in topic.dont %}
+ {% highlight bash %}{{ guide }}{% endhighlight %}
+ {% endfor %}
+ </div>
+ </div>
+ {% endfor %}
+{% endfor %}
diff --git a/_notes/bash.md b/_notes/bash.md
deleted file mode 100644
index dfc7f57..0000000
--- a/_notes/bash.md
+++ /dev/null
@@ -1,208 +0,0 @@
----
-title: Bash
-subtitle: best practices
-layout: plain
----
-
-Arrays
-------
-
-### Declaration
-
-<div class="row">
- <div class="col-md-6" markdown="1">
-
-```bash
-local -a xs=()
-declare -a xs=()
-local -A xs=()
-declare -A xs=()
-
-# Works with nounset:
-echo "${#xs[@]}"
-```
-
- </div>
- <div class="col-md-6" markdown="1">
-
-```bash
-local -a xs
-declare -a xs
-local -A xs
-declare -A xs
-
-# Doesn't work with nounset:
-echo "${#xs[@]}"
-```
-
- </div>
-</div>
-
-### Expansion
-
-<div class="row">
- <div class="col-md-6" markdown="1">
-
-```bash
-func ${arr[@]+"${arr[@]}"}
-```
-
- </div>
- <div class="col-md-6" markdown="1">
-
-```bash
-# Doesn't work with nounset:
-func "${arr[@]}"
-# Doesn't work properly with `declare -a arr=('')`:
-func "${arr[@]+"${arr[@]}"}"
-```
-
- </div>
-</div>
-
-### `unset`
-
-<div class="row">
- <div class="col-md-6" markdown="1">
-
-```bash
-unset -v 'arr[x]'
-unset -v 'arr[$i]'
-```
-
- </div>
- <div class="col-md-6" markdown="1">
-
-```bash
-# May break due to globbing:
-unset -v arr[x]
-# In addition, possible quoting problem:
-unset -v arr[$i]
-# Doesn't work for some reason:
-unset -v 'arr["x"]'
-unset -v 'arr["]"]'
-# Also rejected:
-unset -v 'arr["$i"]'
-
-# An insightful discussion on the topic:
-# https://lists.gnu.org/archive/html/help-bash/2016-09/msg00020.html
-```
-
- </div>
-</div>
-
-`errexit`
----------
-
-I hate this feature, and I especially hate people who prefer "standards" over
-useful behaviour.
-
-### Command substitution
-
-<div class="row">
- <div class="col-md-6" markdown="1">
-
-```bash
-# Without this, bar will be executed w/ errexit disabled!
-shopt -s inherit_errexit
-
-bar() {
- false
- echo 'should never see this' >&2
-}
-
-bar_output="$( bar )"
-foo "$bar_output"
-```
-
- </div>
- <div class="col-md-6" markdown="1">
-
-```bash
-bar() {
- false
- echo 'should never see this' >&2
-}
-
-# Even with errexit, foo will still get executed.
-# More than that, the script will print 'should never see this'!
-foo "$( bar )"
-```
-
- </div>
-</div>
-
-### Process substitution
-
-<div class="row">
- <div class="col-md-6" markdown="1">
-
-```bash
-shopt -s lastpipe
-
-command | while IFS= read -r line; do
- process_line "$line"
-done
-```
-
- </div>
- <div class="col-md-6" markdown="1">
-
-```bash
-# Without lastpipe, you cannot pipe into read:
-command | while IFS= read -r line; do
- process_line "$line"
-done
-```
-
-```bash
-# errexit doesn't work here no matter what:
-while IFS= read -r line; do
- process_line "$line"
-done < <( command )
-echo 'should never see this'
-```
-
-```bash
-# This would break if $output contains the \0 byte:
-output="$( command )"
-
-while IFS= read -r line; do
- process_line "$line"
-done <<< "$output"
-```
-
- </div>
-</div>
-
-### Functions
-
-<div class="row">
- <div class="col-md-6" markdown="1">
-
-```bash
-foo() {
- false
- echo 'should never see this' >&2
-}
-
-foo
-echo ok
-```
-
- </div>
- <div class="col-md-6" markdown="1">
-
-```bash
-# foo will still print 'should never see this'.
-if foo; then
- echo ok
-fi
-
-# Same below.
-foo && echo ok
-foo || echo ok
-```
-
- </div>
-</div>