Add Create And Jump Into A Directory as a Zsh TIL

zsh/create-and-jump-into-a-directory.md

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+# Create And Jump Into A Directory
+
+[Oh My Zsh](https://github.com/ohmyzsh/ohmyzsh) defines a function `take` that
+we can use to both create and `cd` into a directory. If the directory already
+exists, it will simply `cd` into that directory.
+
+```bash
+~/code
+❯ take take-demo
+
+~/code/take-demo
+❯ mkdir already-exists
+
+~/code/take-demo
+❯ take already-exists
+
+~/code/take-demo/already-exists
+❯ cd ..
+
+~/code/take-demo
+❯ take one/two/three
+
+~/code/take-demo/one/two/three
+❯
+```
+
+First `take` creates and `cd`s into `take-demo`. Then `take` only `cd`s into
+`already-exists`. Then we see that `take` can create multiple levels of nested
+directories.
+
+With the help of `which` we can see how `take` is defined:
+
+```bash
+$ which take
+take () {
+        if [[ $1 =~ ^(https?|ftp).*\.tar\.(gz|bz2|xz)$ ]]
+        then
+                takeurl "$1"
+        elif [[ $1 =~ ^([A-Za-z0-9]\+@|https?|git|ssh|ftps?|rsync).*\.git/?$ ]]
+        then
+                takegit "$1"
+        else
+                takedir "$@"
+        fi
+}
+```
+
+We're not dealing with compressed files or git URLs, so we fall through to the
+`else` block with invokes `takedir`.
+
+```bash
+$ which takedir
+takedir () {
+        mkdir -p $@ && cd ${@:$#}
+}
+```
+
+The `mkdir -p $@` is what allows it make new, nested directories and then we
+`cd` to it. The `${@:$#}` is a way of [grabbing the last argument to the
+function](https://stackoverflow.com/a/37601842/535590). This suggests that you
+can pass multiple things to `take`, it will create all of them, and then `cd`
+you into the last one.
+
+[source](https://github.com/ohmyzsh/ohmyzsh/blob/master/lib/functions.zsh#L75-L85)