Someone can tell me what this line is equivalent to?




my guess:

unless ?: is some special operator i'm not familiar with, i'm guessing it's the ternary operator where the true case is omitted.

eg

if (arc -2)
// a = nothing?
else
a = strtod(argv[1], 0);

not sure if that even compiles tbh. is a not assigned anything?

/edit:



A GNU extension to C allows omitting the second operand, and using implicitly the first operand as the second also:
a = x ? : y;
The expression is equivalent to
a = x ? x : y;

This post was edited by carteblanche on Oct 26 2014 06:22pm

yea wikipedia said

is same as

but I don't even understand how arc-2 is can be a condition

This post was edited by bakalolo on Oct 26 2014 06:32pm

It's called a ternary operator...

This post was edited by HighschoolTurd on Oct 26 2014 06:34pm

0 and null return false, everything else returns true iirc

eg it's perfectly fine to say something like:

if (1)

This post was edited by carteblanche on Oct 26 2014 06:36pm

Argc is the number of arguments the application was supplied. 0 and negatives are false, while positives are true. So if argc >=3 then that will return true.

At least if I remember correctly.

hmm i'm pretty sure negatives are true. but it's been a while.

Heh I have no idea. That function would break if he misses arguments as it would return true for -2 and -1.