edit shells slides

slides/shells/shells.md

@@ -2,28 +2,26 @@
 
 - Used as a 'shell' around a bare-ass kernel.
 - People once considered a basic shell user-friendly.
+- Once worked as slow printing.
 
 ## Use Cases
 
-- It's crazy-fast
+- It's crazy-fast to write.
 - Try deleting a file in Python.
-
-## Form
-
-- Big mess of binaries, wrapped together
-- Janky mess
+- It's awful for any structured data.
 
 # Bangs!
 
 Don't say `#!/bin/bash` if you don't mean it!
 
 | Bang!                   | Apraisal      |
-|:---------------|:--------------|
+|:------------------------|:--------------|
 | `#!/bin/bash`           | reasonable    |
 | `#!/bin/sh`             | sensible      |
 | `#!/bin/dash`           | bad idea      |
 | `#!/bin/zsh`            | risky         |
 | `#!/bin/ksh`            | foolish       |
+| `#!/usr/bin/env bash`   | pathetic      |
 | `#!/bin/fish`           | madness       |
 | `#!/bin/elvish`         | genius        |
 
@@ -35,8 +33,9 @@ Protip: for a faster machine, make `sh` a link to `/bin/dash`.
 
 ## `ksh` (korn shell)
 
-- Can be posix compliant with effort.
-- vi mode by default.
+- made before `bash`
+- `vi` mode by default (means you're a hacker)
+- Can be posix compliant with effort
 
 ## `elvish`
 
@@ -46,13 +45,40 @@ Protip: for a faster machine, make `sh` a link to `/bin/dash`.
 - Ctrl+n to search for command arguments
 - Ctrl+l to return to previous locations
 
-## Bash Advantages
+## zsh
+
+- `for x in 1..10`
+
+# Bash Advantages
 
 - Equality check with "==".
     * Dash cannot do `if [ $x == 3 ]; then echo y; fi`
 - `$RANDOM`
 - Dash cannot use `&>/dev/null`
 - No history
+- `$PROMPT_COMMAND`
+
+## Lists
+
+```
+myList+=(*)
+echo "${myList[0]}"
+```
+
+# Functions
+
+
+```
+function wotsa(){
+	def="$(curl -s dict://dict.org/define:$1: | \
+        grep -vP '^\d\d\d ')"
+	if [ "$def" = "" ]; then
+		echo no definition
+	else
+		echo "$def" | mdcat -p
+	fi
+}
+```
 
 # Protips
 
@@ -61,16 +87,22 @@ Protip: for a faster machine, make `sh` a link to `/bin/dash`.
 "\C-x": glob-expand-word
 ```
 
+- `set -e`
+- `set -x`
 - `set -o vi`
 - Ctrl+d
-- `type $whatevre`
+- `type $whatever`
 - `.inputrc`
+- `PS1=foo`
 
 # Fun with Bash
 
 - wifi_qr.sh
 - clean.sh
 - theme.sh
+- notflix.sh
+- clip.sh
+- vidget.sh
 
 # Zen Master Foo