docs/Writerside/topics/compare.h.md

# Compare Functions

The `compare.h` header file contains a collection of compare functions for various primitive types.

They come in two flavors:
- prefixed with `cx_vcmp` they are taking the values directly as arguments
- prefixed with `cx_cmp` the signature is designed to be compatible with the `cx_compare_func` function pointer type.

## Examples

In the following example we use `cx_cmp_int32` as compare function for a `CxList` of `int32_t` values.

```C
CxList *list = cxArrayListCreate(
    cxDefaultAllocator, // use the default allocator
    cx_cmp_int32,       // the compare function for the elements
    sizeof(int32_t),    // the size of one element
    256                 // reseve space for 256 elements
);
```

In the next example we simply want to compare two `double` values with rounding tolerance.
Note how the use of the `cx_vcmp` flavour makes it unnecessary to store the literal in a variable just to be able to take an address.
```C
double x = ...

if (0 == cx_vcmp(x, 47.11)) {
   // do something when equal (except tolerance)
}
```

## List of Functions

```C
#include <cx/compare.h>

// Value Flavour
cx_vcmp_double
cx_vcmp_float
cx_vcmp_int
cx_vcmp_int16
cx_vcmp_int32
cx_vcmp_int64
cx_vcmp_intptr
cx_vcmp_longint
cx_vcmp_longlong
cx_vcmp_uint
cx_vcmp_uint16
cx_vcmp_uint32
cx_vcmp_uint64
cx_vcmp_uintptr
cx_vcmp_ulongint
cx_vcmp_ulonglong

// Pointer Flavour
cx_cmp_double
cx_cmp_float
cx_cmp_int
cx_cmp_int16
cx_cmp_int32
cx_cmp_int64
cx_cmp_intptr
cx_cmp_longint
cx_cmp_longlong
cx_cmp_ptr
cx_cmp_uint
cx_cmp_uint16
cx_cmp_uint32
cx_cmp_uint64
cx_cmp_uintptr
cx_cmp_ulongint
cx_cmp_ulonglong
```

<seealso>
<category ref="apidoc">
<a href="https://ucx.sourceforge.io/api/compare_8h.html">compare.h</a>
</category>
</seealso>