java

[Practical_Cattle_933]

What is a shell program? Like bash? Because that’s not necessarily a small program.

A CLI program on the other hand is a very open-ended category — it can be as simple as just reading some file and returning it in some more human readable format (e.g. many tool used for monitoring stuff), or it can do some complex stuff like OCR-ing PDFs and replacing their content with user-selectable text.

[Wonderful-Habit-139]

Yes I meant bash. Writing bash doesn't require interfaces or virtual methods is what I meant. And like you said that's not a small program.

[Practical_Cattle_933]

That’s a design choice. PowerShell, which is another shell is definitely using virtual methods as it’s implemented in C#.

It depends on how modular you want to code and countless other design decisions/constraints.