Building a GUI that consumes a command line interface turns that command-line USER interface into an APPLICATION PROGRAMMING interface, and that's asking for tr

Building a GUI that consumes a command line interface turns that command-line USER interface into an APPLICATION PROGRAMMING interface, and that's asking for trouble. USER interfaces and PROGRAMMING interfaces are different things, with different, sometimes conflicting purposes and goals. Conflating the two leads to fossilization and confusion for users and application programmers alike. It also causes unnecessary conversion to and from brittle human-readable formats. I'd go a step further and say that software should first and foremost be libraries exposing carefully designed APIs, then have user facing tools (command line and/or GUIs) built upon that.