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What’s a command for counting the lines/characters of all the TypeScript (.ts) files in src?

find «path»: Recursively traverse the given path and list all files in that directory and subdirectories

-name “pattern” option to only match files with a specific pattern (like find . -name "*.java")
(find has many more options! You can look them up online or with man)

wc «file»: Print the number of lines, words, and characters in a file or files

grep «string» «files»: Search a file or files for the given string, print matching lines

-r option that can a directory path and search it recursively (instead of just one or more listed files)

«command» > «file» Save the output of the command in the given file. Overwrites the file!

https://github.com/bluesky-social/social-app

Bluesky, also known as Bluesky Social, is a microblogging social platform and a public benefit corporation. The service is focused on microblogging, and has been called "Twitter-like". Bluesky Social was made open source under the MIT license in May 2023.^[27]

social-app % ls

Dockerfile bskyweb patches

Gemfile docs plugins

LICENSE eas.json scripts

Makefile google-services.json.example src

… a few more files …

* (asterisk, star) Used to create patterns, which expands to all matching paths.�Examples: lib/*.jar, *.txt

echo «args» Print the arguments to the terminal

rev Prints the text of each line reversed

(from a file arg or standard input)

cut -d'«delimeter»' -f «n»

Split each line by delimiter and print the nth element

tail -n <<int>>Take the last n lines of input (file arg or stdin)

head -n <<int>>Take the first n lines of input (file arg or stdin)

sort Print lines in sorted (lexicographic) order

uniq Remove adjacent identical lines from input

What about all of the .ts and .tsx files in src?

xargs «command» perform «command» after reading standard input to get all the command-line arguments

«command» | «command» “pipe” – Take the output of the first command and use it as the input to the second command.

Any other ways to write the example above with | and xargs?

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bash-3.2$ wc /usr/share/dict/words

235976 235976 2493885 /usr/share/dict/words

bash-3.2$ head -n 10 /usr/share/dict/words

aal

aalii

aam

Aani

aardvark

aardwolf

Aaron

bash-3.2$ tail -n 10 /usr/share/dict/words

zymotoxic

zymurgy

Zyrenian

Zyrian

Zyryan

zythem

Zythia

zythum

Zyzomys

Zyzzogeton

What about getting all the file extensions in use across the whole project?

What about counting the number of lines/characters *by file extension*? (e.g. how many lines of .ts code, how many lines of .tsx code)

Another useful resource (if we have time) – there’s a dictionary installed in a plain text file on most operating systems. Anything interesting we can do with it?