Positional arguments are passed as-is after the command name. Order matters.
cat file1.txt file2.txt
Options are named arguments and come in two forms:
-
Short: One-letter options are preceeded by a
-with values placed after (separated by a space).git commit -m "Fix" -
Long: Multi-letter options are preceeded by a
--with values placed after (separated by a=or by a space).git commit --message="Fix"🟰git commit --message "Fix"
Note: Spaces aren't required after options, but are encouranged for readability, because
git commit -m"Fix"looks cramped.
Flags represent boolean values. They are options which don't take a value and can be long or short.
git commit --dry-run -v
When using multiple short flags, you can combine them into one.
ls -a -g -h 🟰 ls -agh 🟰 ls -gha
The order of options/flags does not matter.
ls -a -g 🟰 ls -g -a
However, some commands require all options/flags to come before positional arguments.
❌ ls my-dir -a
✅ ls -a my-dir
Thankfully, most modern commands are agnostic.
git add a.js -v 🟰 git add -v a.js
I prefer to put positional arguments before options/flags when possible, as I find it easier to read.
Quotes are only required for strings that contain special characters (e.g. spaces).
❌ git commit -m Fix thing
✅ git commit -m "Fix thing"
✅ git commit -m Fix
Note: When writing npm scripts, prefer double quotes (
") to single (') for better cross-compatability with Windows.
Many modern command-line programs use a command-subcommand structure. In the following example, git is the root command, and commit is the subcommand.
git commit -m "Hi"
