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docs/command-line-syntax.md

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+# How we document our command line syntax
+
+## Required arguments
+
+Use plain text
+
+_*example:*_
+`gh help`
+help is a required argument in this command
+
+## Placeholder values
+
+Use Angled brackets to represent text that you must supply
+
+_*example:*_
+`gh pr view <issueNumber>`
+Replace `<issueNumber>` with an issue number
+
+## Optional arguments
+
+Place optional arguments in square brackets
+
+_*example:*_
+`gh pr checkout [--web]`
+Replace `--web` is an optional argument
+
+## Mutually exclusive arguments
+
+Place mutually exclusive arguments inside braces separated by a vertical bar.
+
+_*example:*_
+`gh pr {view | create}`
+
+## Repeatable arguements
+
+One or more arguments can replace arguments with ellipsis
+
+_*example:*_
+`gh pr close <numbers … >`