And it made me wonder… What is the consensus on large scripts? What is the largest script you have coded?
Honestly? It was fine. It was well-written and easy to follow and maintain.
I don't think the size of the script (or source code for a proper programming language) is nearly as important as how well-written it is.
If it's a complex program, switch from a scripting language to a compiled language (since compilers give you static type checking, which is useful in large programs).
Scope is important, yes. My point was really just that very large shell scripts can be done in a way that isn't a nightmare.
I agree that if you're doing more complex stuff such as data structures and the like, using a programming language should be the default position.
In this particular case, it was not possible to use Python as that doesn't exist on most the platforms that we needed to support. Using a compiled language was possible, but not desirable, as it would have greatly complicated everything. A shell script really was the least-bad option.
Once the shell script was done doing its thing, the actual application was compiled (by the script), though. The script wasn't doing the main business logic, only installation and configuration.
On the other hand, it would probably make sense to break that script into module-sized smaller scripts. The 'base' script would call those 'module' scripts as and when necessary.
Then each 'module' could be debugged and/or modified separately.