Features for Programming

## Finding Declarations (ctags)

NEdit can process tags files generated using the Unix ctags command or the Exuberant Ctags program. Ctags creates index files correlating names of functions and declarations with their locations in C, Fortran, or Pascal source code files. (See the ctags manual page for more information). Ctags produces a file called "tags" which can be loaded by NEdit. NEdit can manage any number of tags files simultaneously. Tag collisions are handled with a popup menu to let the user decide which tag to use. In 'Smart' mode NEdit will automatically choose the desired tag based on the scope of the file or module. Once loaded, the information in the tags file enables NEdit to go directly to the declaration of a highlighted function or data structure name with a single command. To load a tags file, select "Load Tags File" from the File menu and choose a tags file to load, or specify the name of the tags file on the NEdit command line:

          nedit -tags tags

NEdit can also be set to load a tags file automatically when it starts up. Setting the X resource nedit.tagFile to the name of a tag file tells NEdit to look for that file at startup time (see "Customizing NEdit"). The file name can be either a complete path name, in which case NEdit will always load the same tags file, or a file name without a path or with a relative path, in which case NEdit will load it starting from the current directory. The second option allows you to have different tags files for different projects, each automatically loaded depending on the directory you're in when you start NEdit. Setting the name to "tags" is an obvious choice since this is the name that ctags uses. NEdit normally evaluates relative path tag file specifications every time a file is opened. All accessible tag files are loaded at this time. To disable the automatic loading of tag files specified as relative paths, set the X resource nedit.alwaysCheckRelativeTagsSpecs to False.

To unload a tags file, select "Un-load Tags File" from the File menu and choose from the list of tags files. NEdit will keep track of tags file updates by checking the timestamp on the files, and automatically update the tags cache.

To find the definition of a function or data structure once a tags file is loaded, select the name anywhere it appears in your program (see "Selecting Text") and choose "Find Definition" from the Search menu.