Code-VB supports re-using code as fragments and as modules with procedures in a library.

All procedures from the library are available from Line of Code Builder. In the picture above you see that the library function CharIsLetter seemlessly merges with the list of built-in procedures. Visual Basic typically has a large collection of procedures built-in, so the own collection generally will be rather small. Instead of making thousand+ minor function extensions it is better to create fragments for them (Fragment Editor).
If a procedure is inserted which is not yet included in your project it is added automatically in a module with the same name it has in the library. Not the whole module is copied.
See also:
The procedure library is a folder located by default in the program folder > Code VB (this can be changed in Settings). In here modules (.bas) with procedures are stored, nothing special.
Code-VB > Import File
Code-VB > Export File (or copy file in explorer)
Open the module in editor and add the new code
Use explorer to remove module from folder.