Search order for include files

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1

I have just come across this code that has an improved version of the standard LiquidCrystal library. If I put this library in the recommended library folder then will it be used instead of the built in one when I include it using #include "LiquidCrystal.h" or will this pick up the build in version.
Also will any old code that uses #include <LiquidCrystal.h> still pick up the built in code?

2

If I put this library in the recommended library folder

If, by that, you mean the libraries folder in the sketch directory, then you will have problems, having two LiquidCrystal libraries.

If, by that, you mean replacing the LiquidCrystal library delivered with the IDE, then you won't have a problems, since you'll still only have one LiquidCrystal library.

The issue lies not in search order. It lies in the fact that both libraries folders are searched, and there is no stopping when a particular library is found. The rest of the current folder is searched as well as the other folder.

3

PaulS:
Thanks for the reply PaulS,

If I put this library in the recommended library folder

If, by that, you mean the libraries folder in the sketch directory, then you will have problems, having two LiquidCrystal libraries.
Yes that's what I meant.
If, by that, you mean replacing the LiquidCrystal library delivered with the IDE, then you won't have a problems, since you'll still only have one LiquidCrystal library.

The issue lies not in search order. It lies in the fact that both libraries folders are searched, and there is no stopping when a particular library is found. The rest of the current folder is searched as well as the other folder.
Okay, so it searches all the folders but where will it pluck the final library from? Will it error because both are present or pick the first/last one found. Does using <> instead of "" to enclose the library name effect where the library is searched?

4

Will it error because both are present

That's been my experience.

Does using <> instead of "" to enclose the library name effect where the library is searched?

In terms of "in the current folder" vs. "in the libraries folder", yes. In terms of "in the user libraries folder" vs. "in the core libraries folder", no.

5

Thanks.