I am writing an application to create something out of copybook/copybook fields. So in the panel a user can enter either copybook field name or the copybook itself. I intend to use VER for editing the field name entered. I do want to go to the REXX for editing. VER does not give any direct edit for COBOL or assembler field name like it gives for dataset name. I was thinking of masking the input for each field entered but even I could not find any substring function. Can you please suggest if any option is available for this kind of editing?