compound conditional statements

[beliavsky]

If I have code

if (aa or bb): print "true",

does Python evaluate aa and bb in any particular order? Can I assume that if
aa is true, bb will not be evaluated?

 

[Jeff Epler]

If I have code

if (aa or bb): print "true",

does Python evaluate aa and bb in any particular order? Can I assume that if
aa is true, bb will not be evaluated?

Yes.

For more information, read the language reference:
http://python.org/doc/ref/Booleans.html
The expression x or y first evaluates x; if x is true, its value is
returned; otherwise, y is evaluated and the resulting value is
returned.

Jeff

 

[Jeremy Yallop]

If I have code

if (aa or bb): print "true",

does Python evaluate aa and bb in any particular order?

Yes. `aa' is evaluated first. If it is true, `bb' is not evaluated
and the value of `aa' is the value of the expreesion. If `aa' is
false, the value of `bb' is the value of the expression.

Can I assume that if aa is true, bb will not be evaluated?

Yes.

Jeremy.

 

[Steve Holden]

If I have code

if (aa or bb): print "true",

does Python evaluate aa and bb in any particular order? Can I assume that if
aa is true, bb will not be evaluated?

Yes. Both "and" and "or" are specifcally short-circuiting.

regards