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Make MarkDown easier to parse

Grzegorz Szymaszek
2024-11-03 10:26:47 +01:00
parent 4f5d678e43
commit 63e7e64ddb
1 changed files with 11 additions and 0 deletions
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SC2006.md

@@ -1,20 +1,31 @@
# Use `$(...)` notation instead of legacy backticked `` `...` ``. # Use `$(...)` notation instead of legacy backticked `` `...` ``.
### Problematic code ### Problematic code
```sh ```sh
echo "You are running on `uname`" echo "You are running on `uname`"
``` ```
### Correct code ### Correct code
```sh ```sh
echo "You are running on $(uname)" echo "You are running on $(uname)"
``` ```
### Rationale ### Rationale
Backtick command substitution `` `...` `` is legacy syntax with several issues. Backtick command substitution `` `...` `` is legacy syntax with several issues.
1. It has a series of undefined behaviors related to quoting in POSIX. 1. It has a series of undefined behaviors related to quoting in POSIX.
1. It imposes a custom escaping mode with surprising results. 1. It imposes a custom escaping mode with surprising results.
1. It's exceptionally hard to nest. 1. It's exceptionally hard to nest.
`$(...)` command substitution has none of these problems, and is therefore strongly encouraged. `$(...)` command substitution has none of these problems, and is therefore strongly encouraged.
### Exceptions ### Exceptions
None. None.
### Related resources: ### Related resources:
* [BashFaq: Why is `$(...)` preferred over `` `...` `` (backticks)?](http://mywiki.wooledge.org/BashFAQ/082) * [BashFaq: Why is `$(...)` preferred over `` `...` `` (backticks)?](http://mywiki.wooledge.org/BashFAQ/082)