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[DrDerekDoctors]

Has anyone here written one in C++? I need to make one for my game to basically just evaluate nested logical expressions. i.e. stuff along the lines of:

((a == 2) && (b > 2)) || c == 1

And turn that into a nice tree data structure (so that it can be evaluated repeatedly without re-parsing).

But I'm struggling to find a good source document to learn how to make one. It should be suitable for thicky-thickersons like myself.

Anyone?

[qMopey]

Ya I've done exactly that in C. Let me dig it up... Here it is: http://www.randygaul.net/2015/06/15/parsing-c-style-expressions/
Cheers 

[BorisTheBrave]

Is this for users to use, or to aid in your own development of the game? If the latter, use a scripting language, like Lua, instead. You'll get all the benefits, plus more, and it's easier than writing your own parser.

There's also lots of generators that will create a parser given the grammar definition. But they often a hassle in their own right.

[oahda]

I might recommend going with Boris's suggestion if it makes sense for what you're doing. Otherwise, here's a great set of tutorial that I found recently and posted in the happy programmer room: https://ruslanspivak.com/lsbasi-part1/ c:

[DrDerekDoctors]

Cheers all! I've thought about LUA in the past, maybe I'll look into it again, though, as it would obviously give more flexibility.