Haskell新手求助：如何使用hasktags/fast-tags生成项目标签

Hey there! I totally get the confusion when you're starting out with new tools—let's break this down clearly so you can generate those tags in no time.

First off, the command you're looking at (fast-tags -o tags -R .) gets entered in your terminal/command line (Windows: Command Prompt or PowerShell; Mac/Linux: Terminal app). That's the key part you were missing! Here's a step-by-step for both tools:

Using fast-tags #

1. Open your terminal: Launch the terminal app relevant to your operating system.
2. Navigate to your Haskell project folder: Use the cd command to move into the root directory of your project where your .hs files are stored. For example:

   cd ~/projects/my-haskell-app
   

3. Run the fast-tags command: Enter the exact command you mentioned, and let's break down what each part does so you understand it:

   fast-tags -o tags -R .
   

   • -o tags: Tells fast-tags to output the tag file with the name tags (this is the standard name most editors look for).
   • -R: Enables recursive scanning of all subdirectories under the path you specify.
   • .: The dot means "current directory"—so fast-tags will look for every .hs file in your project folder and all its subfolders.
4. Check the result: After running the command, you'll see a new tags file in your project root. Most code editors (like Vim, Emacs, VS Code with the right extensions) will automatically detect this file and let you jump to function/type definitions using it.

Using hasktags #

Since you also installed hasktags, here's how to use it similarly:

1. Follow steps 1-2 above: Open your terminal and navigate to your project folder.
2. Run the basic hasktags command: The most common usage to generate a standard tags file (ctags format, which works with most editors) is:

   hasktags -c .
   

   • -c: Specifies we want to generate ctags-compatible output.
   • .: Again, targets the current directory and all subdirectories.
3. Customize if needed: If you want to specify a different output file name, add the -o flag just like with fast-tags:

   hasktags -o my-custom-tags -c .
   

   Hasktags also supports etags format (for Emacs) with the -e flag instead of -c.

Quick Troubleshooting Tip #

If you get an error like "command not found" when running either tool, it might mean the tool's executable isn't in your system's PATH. But since you said you already installed them, double-check that you're running the command from a terminal session that has access to the installed tools (sometimes you need to restart your terminal after installing new command-line tools).

内容的提问来源于stack exchange，提问作者Cyrus