What's the preferred Pascal file extension?

Is it:

• .p
• .pl
• .pas
• .pascal

Or something else?

And will the various Pascal compilers (notably fpc) bork if you don't use the preferred开发者_JS百科 extension?

The most common file extension for Pascal is pas. As for FPC, it uses the pp extension to denote FPC-specific code.

I think there is not a "preferred" extension, but you can't miss by using pas.

.pl is a bad idea, because it will conflict with both perl and prolog programs.

According to the Wikipedia .pp, .pas, .inc are valid (last one for include files).

You may also check FreePascal Wiki, which describe .pas as

Unit with Pascal code (typically for a form stored in a corresponding *.lfm file)

and .pp as

Pascal code

I believe you should use one of these two depending of your own preferences.