Re: MODULEand USE versus Argument Passing

E. Robert Tisdale wrote:

(snip)

Global variables are *always* a bad idea.
Never pass function arguments through modules or common storage.


There is an old saying that goes something like "All generalizations
are bad, including this one."

I would agree that global variables are often overused.
There are cases where the whole program revolves around certain
variables, usually arrays. In those cases, it sometimes makes
sense. COMMON, though, requires compile time dimensions which isn't
so convenient in many cases. In C one would use a global pointer variable. I am not sure that Fortran allows either pointers or
ALLOCATABLE data in COMMON, but it might.

The general rule that the code should be written so that it
is easiest to understand still applied.  Sometimes that means
global variables.

-- glen

.

Relevant Pages

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  • Re: MODULEand USE versus Argument Passing
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