Customizing the File Header Comment and Other Text Macros in Xcode 9
Xcode 9 allows you to customize the file header and other so-called text macros using a plist file. The process is described in Xcode Help on a page titled Customize text macros.
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See Text macros reference below for a full list of available macros. You can use other text macros in your value by wrapping them with three underscores, such as
___DATE___
. See Text macro format reference below.
Previously, you had to edit various template files or use defaults write.