updates for version 2.0

Author: learnbyexample

LICENSE

@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2019 Sundeep Agarwal
+Copyright (c) 2023 Sundeep Agarwal
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

README.md

@@ -1,12 +1,10 @@
-# GNU GREP and RIPGREP
+# CLI text processing with GNU grep and ripgrep
 
-Example based guide to mastering GNU grep and ripgrep.
+Example based guide to mastering GNU grep and ripgrep. Visit https://youtu.be/MSbGokwHm-A for a short video about the book.
 
-<p align="center">
-    <img src="./images/grep.png" width="320px" height="400px" />
-</p>
+<p align="center"><img src="./images/grep_ls.png" alt="CLI text processing with GNU grep and ripgrep ebook cover image" /></p>
 
-The book also includes exercises to test your understanding, which are presented together as a single file in this repo - [Exercises.md](./exercises/Exercises.md)
+The book also includes exercises to test your understanding, which are presented together as a single file in this repo — [Exercises.md](./exercises/Exercises.md)
 
 For solutions to the exercises, see [Exercise_solutions.md](./exercises/Exercise_solutions.md).
 
@@ -18,37 +16,35 @@ See [Version_changes.md](./Version_changes.md) to keep track of changes made to
 
 # E-book
 
-You can purchase the pdf/epub versions of the book using these links:
+* You can purchase the pdf/epub versions of the book using these links:
+    * https://learnbyexample.gumroad.com/l/gnugrep_ripgrep
+    * https://leanpub.com/gnugrep_ripgrep
+* You can also get the book as part of these bundles:
+    * **All books bundle** bundle from https://learnbyexample.gumroad.com/l/all-books
+        * Includes all my programming books
+    * **Magical one-liners** bundle from https://learnbyexample.gumroad.com/l/oneliners or https://leanpub.com/b/oneliners
+    * **Awesome Regex** bundle from https://learnbyexample.gumroad.com/l/regex or https://leanpub.com/b/regex
+* See https://learnbyexample.github.io/books/ for a list of other books
 
-* https://learnbyexample.gumroad.com/l/gnugrep_ripgrep
-* https://leanpub.com/gnugrep_ripgrep
-
-You can also get the book as part of these bundles:
-
-* **Magical one-liners** bundle from https://learnbyexample.gumroad.com/l/oneliners or https://leanpub.com/b/oneliners
-* **Awesome Regex** bundle from https://learnbyexample.gumroad.com/l/regex or https://leanpub.com/b/regex
-* **All books bundle** bundle from https://learnbyexample.gumroad.com/l/all-books
-    * Includes all my programming books
-
-See https://learnbyexample.github.io/books/ for a list of other books
-
-For a preview of the book, see [sample chapters](https://github.com/learnbyexample/learn_gnugrep_ripgrep/blob/master/sample_chapters/gnu_grep_sample.pdf)
+For a preview of the book, see [sample chapters](./sample_chapters/gnu_grep_sample.pdf).
 
 The book can also be [viewed as a single markdown file in this repo](./gnu_grep.md). See my blogpost on [generating pdfs from markdown using pandoc](https://learnbyexample.github.io/tutorial/ebook-generation/customizing-pandoc/) if you are interested in the ebook creation process.
 
 For the web version of the book, visit https://learnbyexample.github.io/learn_gnugrep_ripgrep/
 
 <br>
 
-# Feedback
+# Feedback and Contributing
 
-[Open an issue](https://github.com/learnbyexample/learn_gnugrep_ripgrep/issues) if you spot any typo/errors.
+⚠️ ⚠️ Please DO NOT submit pull requests. Main reason being any modification requires changes in multiple places.
 
-:warning: :warning: Please DO NOT submit pull requests. Main reason being any modification requires changes in multiple places.
+I would highly appreciate if you'd let me know how you felt about this book. It could be anything from a simple thank you, pointing out a typo, mistakes in code snippets, which aspects of the book worked for you (or didn't!) and so on. Reader feedback is essential and especially so for self-published authors.
 
-I'd also highly appreciate your feedback about the book.
+You can reach me via:
 
-Twitter: https://twitter.com/learn_byexample
+* Issue Manager: [https://github.com/learnbyexample/learn_gnugrep_ripgrep/issues](https://github.com/learnbyexample/learn_gnugrep_ripgrep/issues)
+* E-mail: `echo 'bGVhcm5ieWV4YW1wbGUubmV0QGdtYWlsLmNvbQo=' | base64 --decode`
+* Twitter: [https://twitter.com/learn_byexample](https://twitter.com/learn_byexample)
 
 <br>
 
@@ -72,15 +68,14 @@ Twitter: https://twitter.com/learn_byexample
 
 * [GNU grep documentation](https://www.gnu.org/software/grep/manual/grep.html) — manual and examples
 * [ripgrep](https://github.com/BurntSushi/ripgrep) — user guide and examples
-* [stackoverflow](https://stackoverflow.com/) and [unix.stackexchange](https://unix.stackexchange.com/) — for getting answers to pertinent questions on `bash`, `grep` and other commands
+* [stackoverflow](https://stackoverflow.com/) and [unix.stackexchange](https://unix.stackexchange.com/) — for getting answers to pertinent questions on `grep` and related commands
 * [tex.stackexchange](https://tex.stackexchange.com/) — for help on [pandoc](https://github.com/jgm/pandoc/) and `tex` related questions
-* Cover image
-    * [LibreOffice Draw](https://www.libreoffice.org/discover/draw/)
-    * [detective](https://www.flickr.com/photos/32068925@N08/3028314931) by [olarte.ollie](https://www.flickr.com/photos/ollieolarte/) under [Creative Commons Attribution-Share Alike 2.0 Generic](https://creativecommons.org/licenses/by-sa/2.0/)
-* [pngquant](https://pngquant.org/) and [svgcleaner](https://github.com/RazrFalcon/svgcleaner) for optimizing images
-* [softwareengineering.stackexchange](https://softwareengineering.stackexchange.com/questions/39/whats-your-favourite-quote-about-programming) and [skolakoda](https://skolakoda.org/programming-quotes) for programming quotes
+* [/r/commandline/](https://old.reddit.com/r/commandline), [/r/linux4noobs/](https://old.reddit.com/r/linux4noobs/), [/r/linuxquestions/](https://old.reddit.com/r/linuxquestions/) and [/r/linux/](https://old.reddit.com/r/linux/) — helpful forums
+* [canva](https://www.canva.com/) — cover image
+* [oxipng](https://github.com/shssoichiro/oxipng), [pngquant](https://pngquant.org/) and [svgcleaner](https://github.com/RazrFalcon/svgcleaner) — optimizing images
 * [Warning](https://commons.wikimedia.org/wiki/File:Warning_icon.svg) and [Info](https://commons.wikimedia.org/wiki/File:Info_icon_002.svg) icons by [Amada44](https://commons.wikimedia.org/wiki/User:Amada44) under public domain
-* [Andrew Gallant](https://blog.burntsushi.net/about/) (author of `ripgrep`) and [mikeblas](https://www.reddit.com/user/mikeblas) for critical feedback
+* [carbon](https://carbon.now.sh/) — creating terminal screenshots with highlighted text
+* [Andrew Gallant](https://blog.burntsushi.net/about/) (author of `ripgrep`), [mikeblas](https://old.reddit.com/user/mikeblas) and [Pound-Hash](https://github.com/Pound-Hash) for critical feedback
 * [mdBook](https://github.com/rust-lang/mdBook) — for web version of the book
     * [mdBook-pagetoc](https://github.com/JorelAli/mdBook-pagetoc) — for adding table of contents for each chapter
     * [minify-html](https://github.com/wilsonzlin/minify-html) — for minifying html files
@@ -91,6 +86,7 @@ Special thanks to all my friends and online acquaintances for their help, suppor
 
 # License
 
-The book is licensed under a [Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License](https://creativecommons.org/licenses/by-nc-sa/4.0/)
+The book is licensed under a [Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License](https://creativecommons.org/licenses/by-nc-sa/4.0/).
+
+The code snippets are licensed under MIT, see [LICENSE](./LICENSE) file.
 
-The code snippets are licensed under MIT, see [LICENSE](./LICENSE) file

Version_changes.md

@@ -1,5 +1,21 @@
 <br>
 
+### 2.0
+
+* Command versions updated to **GNU grep 3.10** and **ripgrep 13.0.0**
+* Many more exercises added, and you can practice some of them using this [interactive TUI app](https://github.com/learnbyexample/TUI-apps/blob/main/GrepExercises)
+* PCRE chapter — added section for conditional grouping, corrected description and examples for `\K`, atomic grouping, etc
+* ripgrep chapter — options and regex section modified to present only differences compared to `GNU grep`, added details for more options such as `--field-match-separator`, improved recursive search section, etc
+* Long sections split into smaller ones
+* In general, many of the examples, exercises, solutions, descriptions and external links were updated/corrected
+* Updated Acknowledgements section
+* Code snippets related to info/warning sections will now appear as a single block
+* Book title changed to **CLI text processing with GNU grep and ripgrep**
+* New cover image
+* Images centered for EPUB format
+
+<br>
+
 ### 1.7
 
 * Command versions updated to **GNU grep 3.6** and **ripgrep 12.1.1**

code_snippets/BRE_ERE_Regular_Expressions.sh

@@ -1,46 +1,52 @@
 ## Line Anchors
 
-printf 'spared no one\npar\nspar\ndare' | grep '^pa'
+cat anchors.txt
 
-printf 'spared no one\npar\nspar\ndare' | grep 'ar$'
+grep '^s' anchors.txt
+
+grep 'rt$' anchors.txt
 
 printf 'spared no one\npar\nspar\ndare' | grep '^par$'
 
 printf 'spared no one\npar\nspar\ndare' | grep -x 'par'
 
 ## Word Anchors
 
-cat word_anchors.txt
+cat anchors.txt
+
+grep '\bpar' anchors.txt
 
-grep '\bpar' word_anchors.txt
+grep 'par\b' anchors.txt
 
-grep 'par\b' word_anchors.txt
+grep '\bpar\b' anchors.txt
 
-grep '\bpar\b' word_anchors.txt
+grep -w 'par' anchors.txt
 
-grep -w 'par' word_anchors.txt
+## Opposite Word Anchor
 
-grep '\Bpar\B' word_anchors.txt
+grep '\Bpar\B' anchors.txt
 
-grep '\Bpar' word_anchors.txt
+grep '\Bpar' anchors.txt
 
-grep 'par\B' word_anchors.txt
+grep 'par\B' anchors.txt
 
 ## Alternation
 
-printf 'I like cats\nI like parrots\nI like dogs' | grep 'cat\|dog'
+cat pets.txt
 
-printf 'I like cats\nI like parrots\nI like dogs' | grep -E 'cat|dog'
+grep 'cat\|dog' pets.txt
 
-printf 'I like cats\nI like parrots\nI like dogs' | grep -e 'cat' -e 'dog'
+grep -E 'cat|dog' pets.txt
+
+grep -e 'cat' -e 'dog' pets.txt
 
 printf 'CATs dog bee parrot FoX' | grep -ioE 'cat|dog|fox'
 
-grep -E '^a|e\b' word_anchors.txt
+grep -E '^t|ar\b' anchors.txt
 
-grep --color=auto -E '^|pare' word_anchors.txt
+grep --color -E 'sub|for|tar|' anchors.txt
 
-grep --color=auto -E 'sub|put|tar|$' word_anchors.txt
+## Alternation precedence
 
 echo 'car spared spar' | grep -oE 'are|spared'
 
@@ -54,15 +60,15 @@ echo 'pool party 2' | grep -oP 'par|party'
 
 ## Grouping
 
-printf 'red\nreform\nread\narrest' | grep -E 'reform|rest'
+printf 'red\nreform\nread\ncrest' | grep -E 'reform|rest'
 
-printf 'red\nreform\nread\narrest' | grep -E 're(form|st)'
+printf 'red\nreform\nread\ncrest' | grep -E 're(form|st)'
 
-printf 'sub par\nspare\npart time' | grep -E '\bpar\b|\bpart\b'
+grep -E '\bpar\b|\bpart\b' anchors.txt
 
-printf 'sub par\nspare\npart time' | grep -E '\b(par|part)\b'
+grep -E '\b(par|part)\b' anchors.txt
 
-printf 'sub par\nspare\npart time' | grep -E '\bpar(|t)\b'
+grep -E '\bpar(|t)\b' anchors.txt
 
 ## Escaping metacharacters
 
@@ -80,21 +86,23 @@ printf '(a/b) + c\n3 + (a/b) - c' | grep -E '^\(a/b)'
 
 ## Matching characters like tabs
 
-echo 'attempt' | grep -o 'a\tt'
-
 printf 'go\tto\ngo to' | grep $'go\tto'
 
 printf 'go\tto\ngo to' | grep $'go\x20to'
 
-## The dot meta character
+echo 'sea eat car rat eel tea' | grep 's\ea'
+
+## The dot metacharacter
 
 echo 'tac tin cot abc:tuv excite' | grep -o 'c.t'
 
 printf '42\t33\n'
 
 printf '42\t33\n' | grep -o '2.3'
 
-grep -xE 'c..(t|l)y' words.txt
+wc -l words.txt
+
+grep -xE 'du.(ky|ts)' words.txt
 
 ## Quantifiers
 
@@ -126,21 +134,27 @@ echo 'abc ac adc abbc xabbbcz bbb bc abbbbbc' | grep -oE 'ab{,2}c'
 
 echo 'abc ac adc abbc xabbbcz bbb bc abbbbbc' | grep -oE 'ab{3}c'
 
+echo 'a{5} = 10' | grep -E 'a\{5}'
+
+echo 'report_{a,b}.txt' | grep -E '_{a,b}'
+
+## Conditional AND
+
 echo 'Error: not a valid input' | grep -o 'Error.*valid'
 
-echo 'a cat and a dog' | grep -E 'cat.*dog|dog.*cat'
+echo 'cat and dog and parrot' | grep -oE 'cat.*dog|dog.*cat'
 
-echo 'dog and cat' | grep -E 'cat.*dog|dog.*cat'
+echo 'dog and cat and parrot' | grep -oE 'cat.*dog|dog.*cat'
 
 ## Longest match wins
 
 echo 'foot' | grep -oE 'f.?o'
 
 echo 'car bat cod map scat dot abacus' | grep -o '.*'
 
-echo 'foo123312baz' | grep -oE 'o(1|2|3)+(12baz)?'
+echo 'fig123312apple' | grep -oE 'g(1|2|3)+(12apple)?'
 
-echo 'foo123312baz' | grep -oP 'o(1|2|3)+(12baz)?'
+echo 'fig123312apple' | grep -oP 'g(1|2|3)+(12apple)?'
 
 echo 'car bat cod map scat dot abacus' | grep -o '.*m'
 
@@ -160,6 +174,8 @@ echo 'do so in to no on' | grep -ow '[sot][on]'
 
 grep -xE '[on]{2,}' words.txt
 
+## Character class metacharacters
+
 echo 'Sample123string42with777numbers' | grep -oE '[0-9]+'
 
 echo 'coat Bin food tar12 best' | grep -owE '[a-z]+'
@@ -176,19 +192,25 @@ echo '0501 035 154 12 26 98234' | grep -owE '0*[1-9][0-9]{2,}'
 
 echo 'Sample123string42with777numbers' | grep -oE '[^0-9]+'
 
-echo 'foo=42; baz=123' | grep -o '^[^=]*'
+echo 'apple:123:banana:cherry' | grep -o '^[^:]*'
 
-echo 'foo:123:bar:baz' | grep -oE '(:[^:]+){2}$'
+echo 'apple:123:banana:cherry' | grep -oE '(:[^:]+){2}$'
 
 echo 'I like "mango" and "guava"' | grep -oE '"[^"]+"'
 
 printf 'tryst\nfun\nglyph\npity\nwhy' | grep -xE '[^aeiou]*'
 
 printf 'tryst\nfun\nglyph\npity\nwhy' | grep -v '[aeiou]'
 
+## Escape sequence sets
+
 printf 'load;err_msg--\nant,r2..not\n' | grep -o '\w*'
 
-printf '   1..3  \v\f  foo_baz 42\tzzz   \r\n1-2-3\n\n' | grep -o '\S*'
+echo 'sea eat car rat eel tea' | grep -o '\b\w' | paste -sd ''
+
+printf '   1..3  \v\f  fig_tea 42\tzzz   \r\n1-2-3\n\n' | grep -o '\S*'
+
+## Named character sets
 
 printf 'err_msg\nxerox\nant\nm_2\nP2\nload1\neel' | grep -x '[[:lower:]]*'
 
@@ -198,11 +220,13 @@ printf 'err_msg\nxerox\nant\nm_2\nP2\nload1\neel' | grep -x '[[:alnum:]]*'
 
 echo 'pie tie#ink-eat_42;' | grep -o '[^[:punct:]]*'
 
+## Matching character class metacharacters literally
+
 echo 'ab-cd gh-c 12-423' | grep -owE '[a-z-]{2,}'
 
-printf 'int a[5]\nfoo\n1+1=2\n' | grep '[=]]'
+printf 'int a[5]\nfig\n1+1=2\n' | grep '[=]]'
 
-printf 'int a[5]\nfoo\n1+1=2\n' | grep '[]=]'
+printf 'int a[5]\nfig\n1+1=2\n' | grep '[]=]'
 
 echo 'int a[5]' | grep '[x[.y]'
 

code_snippets/Context_matching.sh

@@ -2,22 +2,22 @@ cat context.txt
 
 ## -A
 
-grep -A2 'blue' context.txt
-
 grep -x -A2 'blue' context.txt
 
+grep -A2 'blue' context.txt
+
 ## -B
 
 grep -B2 'bread' context.txt
 
 grep -B3 'ruby' context.txt
 
+grep -A1 -B2 'sky' context.txt
+
 ## -C
 
 grep -C1 'sky' context.txt
 
-grep -A1 -B2 'sky' context.txt
-
 grep -C2 'kotlin' context.txt
 
 ## Contiguous matches