Inline error

[fuzzball27]

I'm running a couple of inline functions to determine minimum and maximum values, and I'm getting an error that says "variable name expected" for the functions...any ideas as to why it isn't working? (I got these functions from Power Programming)

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inline int min(int v1, intv2) {
	return (v1 < v2) ? v1 : v2;
}

inline int max(int v1, int v2) {
	return (v1 > v2) ? v1 : v2;
}

# Status: NXC processing global declarations
# Status: NXC processing pr# Error: Variable name expected
File "../build/PROGRAM.nxc" ; line 15
# inline void min(int v1, intv2) {
#----------------------------------------------------------

[HaWe]

a typo: intv2 => int v2.
And then maybe try it like this way (int or long instead of float):

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inline float min(float a, float b) {
  return (a<b? a: b);
}

inline float max(float a, float b) {
  return (a>b? a: b);
}

[fuzzball27]

Thanks! It's working.

[muntoo]

I'd rather use #defines, as we don't have voids as function parameters yet. This ensures "compatibility" (call it what you will) between all types which support the < and > operators:

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#define min(a,b) (a<b?a:b)
#define max(a,b) (a>b?a:b)

IMHO, I think this should be built into NXCDefs.h. (Or NXTDefs.h, NBCCommon.h, take your pick.)

[HaWe]

muntoo,
I don't understand what should be better with your #inline definition and *our* inline int or inline float? Can you give me some programming examples?

[muntoo]

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float x = min(20.2, 20.1);
// x = 20;

If min() was:

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inline long min(long a, long b)
{
    return(a < b ? a : b);
}

It wouldn't give you the expected result.

If we'd used inline float min(float a, float b) instead, min() would be limited in range whenever you wanted to use a long.

-----

If we had C++, I could use templates.

[HaWe]

I don't know if I understand you correctly, but I guess what you might mean is:
if we use
#define min(a,b) (a<b?a:b)
#define max(a,b) (a>b?a:b)

we will be not limited to any pre-defined varible types like int, long, float, this macro will work with each variable type for each macro call - correct?

[muntoo]

we will be not limited to any pre-defined varible types like int, long, float, this macro will work with each variable type for each macro call - correct?

Yeah, that's what I mean.

[mightor]

Here are some #defines for min and max for 3 numbers:

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#define min3(a, b, c) (a < b) ? ((a < b) ? a : c) : ((b < c) ? b : c)
#define max3(a, b, c) (a > b) ? ((a > c) ? a : c) : ((b > c) ? b : c)

I use these and the ones in the earlier post in my driver suite.

- Xander

[muntoo]

Here are some #defines for min and max for 3 numbers:

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#define min3(a, b, c) (a < b) ? ((a < b) ? a : c) : ((b < c) ? b : c)
#define max3(a, b, c) (a > b) ? ((a > c) ? a : c) : ((b > c) ? b : c)

For reference, the exact equivalents are:

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#define min(a,b) (a<b?a:b)
#define max(a,b) (a>b?a:b)

#define min3(a,b,c) min(a,min(b,c))
#define max3(a,b,c) max(a,max(b,c))

Although they're less optimized.