From 8dad13155f728a1d44b21bbf047dc048ae101253 Mon Sep 17 00:00:00 2001
From: Michele Cereda <cereda.michele@gmail.com>
Date: Fri, 25 Oct 2024 21:13:17 +0200
Subject: [PATCH] chore(snippets): how to print the last field of strings

---
 knowledge base/awk.md                       |  9 ++++---
 knowledge base/grep.md                      | 26 +++++++++++----------
 snippets/print the last field of strings.sh | 11 +++++++++
 3 files changed, 31 insertions(+), 15 deletions(-)
 create mode 100644 snippets/print the last field of strings.sh

diff --git a/knowledge base/awk.md b/knowledge base/awk.md
index ab9c390..9d760cf 100644
--- a/knowledge base/awk.md	
+++ b/knowledge base/awk.md	
@@ -1,7 +1,5 @@
 # `awk`
 
-## Table of contents <!-- omit in toc -->
-
 1. [TL;DR](#tldr)
 1. [Further readings](#further-readings)
 
@@ -24,6 +22,10 @@ awk 'length($0) > 20' sales.txt
 
 # Print only lines where the value of the second column is greater than 100.
 awk '$2 > 100' sales.txt
+
+# Print only the last column.
+echo 'maps.google.com' | awk -F. '{print $NF}'
+awk -F '/' '{print $NF}' <<< 'test/with/slashes'
 ```
 
 ## Further readings
@@ -33,7 +35,8 @@ awk '$2 > 100' sales.txt
 - [The essential Bash cheat sheet]
 
 <!--
-  References
+  Reference
+  ═╬═Time══
   -->
 
 <!-- Others -->
diff --git a/knowledge base/grep.md b/knowledge base/grep.md
index 8562fc5..2c8fd40 100644
--- a/knowledge base/grep.md	
+++ b/knowledge base/grep.md	
@@ -1,14 +1,12 @@
 # Grep
 
-## Table of contents <!-- omit in toc -->
-
 1. [TL;DR](#tldr)
 1. [Variants](#variants)
    1. [Archive-related variants](#archive-related-variants)
    1. [PDFgrep](#pdfgrep)
 1. [Gotchas](#gotchas)
 1. [Further readings](#further-readings)
-1. [Sources](#sources)
+   1. [Sources](#sources)
 
 ## TL;DR
 
@@ -33,6 +31,10 @@ find . -type f -print0 | xargs -0 -n 1 -P "$(nproc)" grep 'pattern'
 
 # Highlight numbers in strings.
 grep --color '[[:digit:]]' 'file.txt'
+
+# Only print text after a delimiter.
+echo "string,with,delimiters" | grep -o '[^,]*$'
+echo "string/with/delimiters" | grep -o '[^/]*$'
 ```
 
 ## Variants
@@ -52,8 +54,10 @@ grep --color '[[:digit:]]' 'file.txt'
 
 For simple searches, you might want to use [pdfgrep].
 
-Should you need more advanced grep capabilities not incorporated by pdfgrep, you might want to convert the file to text and search there.<br/>
-You can to this using [pdftotext](pdfgrep.md) as shown in this example ([source][stackoverflow answer about how to search contents of multiple pdf files]):
+Should you need more advanced grep capabilities not incorporated by pdfgrep, you might want to convert the file to text
+and search there.<br/>
+You can to this using [pdftotext](pdfgrep.md) as shown in this example
+([source][how to search contents of multiple pdf files]):
 
 ```sh
 find /path -name '*.pdf' -exec sh -c 'pdftotext "{}" - | grep --with-filename --label="{}" --color "your pattern"' ';'
@@ -76,26 +80,24 @@ find /path -name '*.pdf' -exec sh -c 'pdftotext "{}" - | grep --with-filename --
 - [Grep the standard error stream]
 - [`pdfgrep`][pdfgrep]
 
-## Sources
-
-All the references in the [further readings] section, plus the following:
+### Sources
 
 - Answer on [StackOverflow] about [how to search contents of multiple pdf files]
 - [Regular expressions in grep with examples]
 - [Parallel grep]
+- [How to find the last field using `cut`]
 
 <!--
-  References
+  Reference
+  ═╬═Time══
   -->
 
-<!-- In-article sections -->
-[further readings]: #further-readings
-
 <!-- Knowledge base -->
 [grep the standard error stream]: grep%20the%20standard%20error%20stream.md
 [pdfgrep]: pdfgrep.md
 
 <!-- Others -->
+[how to find the last field using `cut`]: https://stackoverflow.com/questions/22727107/how-to-find-the-last-field-using-cut#22727242
 [how to search contents of multiple pdf files]: https://stackoverflow.com/a/4643518
 [parallel grep]: https://www.highonscience.com/blog/2021/03/21/parallel-grep/
 [regular expressions in grep with examples]: https://www.cyberciti.biz/faq/grep-regular-expressions/
diff --git a/snippets/print the last field of strings.sh b/snippets/print the last field of strings.sh
new file mode 100644
index 0000000..bcf7582
--- /dev/null
+++ b/snippets/print the last field of strings.sh	
@@ -0,0 +1,11 @@
+#!/usr/bin/sh
+
+# Ordered best to worst experience
+
+echo "string/with/delimiters" | awk -F '/' '{print $NF}'
+echo "string/with/delimiters" | sed 's|^.*/||'
+echo "string/with/delimiters" | choose -f '/' -1
+echo "string/with/delimiters" | grep -o --color='never' '[^/]*$'
+echo "string/with/delimiters" | perl -pe 's|(.*)/(.*)$|$2|' -
+echo "string/with/delimiters" | tr '/' '\n' | tail -n1
+echo "string/with/delimiters" | rev | cut -d '/' -f '1' | rev