Executable XML users challenge

provide any LISP macro with clear explanation of its structure and function
that is :
1.concise (max 10 lines)
2.does not have a C equivalent(at least not anything above 100 lines)
3.does not use any libraries or imported complex functions which are not in C
If you provide an exact explanation/commentary on what it does i'll try to make a C solution which
is equivalent to LISP one. If i fail to do so, LISP wins, if i provide a solution you can make another macro.
If all examples in the thread are provide with C equivalents, LISP loses.

>>38
#define square(x) ((x) * (x))

square(rand() % 10) expands to ((rand() % 10) * (rand() % 10)). The macro is for when you only want the argument to be evaluated once, and then you use the returned value in the body of the macro.

Add syntax to C using the preprocessor.

>>41
if you want the rand() function to be evaluated once and this used for such cases, you easily use a function
inline int square(int x){int y=x; return y*y;}

Hey FV, what's your job?

>>44
I'm a free artist

>>45
And what "a free artist" does for living?

for ints:
square(int x){return x*x;}
for floats:
fsquare(float x){return x*x}
for doubles:
dsquare(double x){return x*x}

>>46
Anything he likes.

>>48
And how do earn money? You parents?

>>46
wastes welfare

I don't have a job
Just say it, bro

>>45
read: free autist

>>52
Should autists really be allowed to roam free?

>>53
As long as they don't invent any programming languages they are relatively harmless.

>>39
>list with floating point numbers and integers
Why are you storing the array of floats and ints at the same place?

>>55
to irk your static typed shit,
duh.
inb4 void*

>>56
I would just use 2 arrays and sort them separetely, with most effective sort speciazlied for the specific type.
using a mixed type array(actually an array of pointers for each element, incredibly bloated compared to int array)
make any comparison
1.first check the type of element
2.convert to common comparator type
3.compare and return result in common type
vs
1.compare two elements

>>57
Thats just an excuse. You can't write such code in C.

>>58
int i;
#define STDMAIN main(int argc,char**argv){;
#define STDEND ;return 0;};
#define cs4p const int*
#define cf8p const double*
#define sort(array,function) qsort((void*)array, sizeof(array)/sizeof(array[0]),sizeof(array[0]),function)
#define printints(array) ;for(i=0;i<(sizeof(array)/sizeof(array[0]));i++){printf("%d ",array[i]);};puts("");
#define printdoubles(array) ;for(i=0;i<(sizeof(array)/sizeof(array[0]));i++){printf("%f ",array[i]);};puts("");
#define printevens(array) ;for(i=0;i<(sizeof(array)/sizeof(array[0]));i++){if(!(array[i]&1))printf("%d ",array[i]);};puts("");
#define printodds(array) ;for(i=0;i<(sizeof(array)/sizeof(array[0]));i++){if((array[i]&1))printf("%d ",array[i]);};puts("");
#define sortpd(array,function) sort(array,function);printdoubles(array);
#define sortp(array,function) sort(array,function);printints(array);

#include <stdio.h>
#include <stdlib.h>
int cmpn(cs4p num1,cs4p num2){return *num1-*num2;}
int cmpr(cs4p num1,cs4p num2){return *num2-*num1;}
int dcmpn(cf8p a,cf8p b){return (*a>*b)- (*a<*b);}

STDMAIN;//i'm not going to re/allocate anything useless at run-time.
int intarr[]={6,5,9,2,1,8};
double doublearr[]={2.0,0.0,4.5};
sortpd(doublearr,dcmpn);
sort(intarr,cmpn);
printodds(intarr);
printevens(intarr);
puts("hello world");
STDEND

>>59
#define STDMAIN main(int argc,char**argv){;
why the fuck. why is function macro define srsly wtf.
SexuallyTransmittedDiseaseMAIN

>>60
STanDardMAIN
STanDardEND(Program)

>>61
I know what it's supposed to mean.
I'm just asking why the fuck would you define every function as a macro.

>>62
To make reusable code. I could stick those macro in void.h and use them for years.

>>62
consider writing 1000 C files, each could be started with
int main(int argc,char**argv){;
or
STDMAIN
which one would be easier?

>>59
so you are still arguing that C can do anything LISP does in an elegant way? I can't see an array of floats, ints in your code. it does not create a sorted array, just prints a string. and lisp code is like in two lines yet your (insufficent) C version is huge
also
(*a>*b)- (*a<*b)
lol

to make 1000 empty C files with same exact line #include <void.h> is left as exercise to the reader.

>>64
The one where I don't use C I use scheme because I'm not programming for an 8-bit embedded microcontroller.

>>65
>(*a>*b)- (*a<*b)
see http://dis.4chan.org/read/prog/1320462348/5-6

>>68
why simply it is not *a-*b

>>63
I could stick those macro in void.h
Why did I even ask -_-
stick your dick in void.h get STD

>>69
doubles don't return 0, they return double 0.0

Your macros expands wrong half the time you know it right? for example

if(test)printints(array);
will expand like
if(test);for(i=0;i<(sizeof(array)/sizeof(array[0]));i++){printf("%d ",array[i]);};puts("");

do you really know C?

the type of return of *a-*b is double, and qsort expects the return of function to be integer.

>>72
I don't use such style:
if(test){printints(array); }

>>71
qsort is not stable, why do you even care equality?

If you expect to use short function syntax, write inline versions.
These are designed to avoid typing ;;; each time.

>>75
Its a comparator function which follow the standard qsort return type
1 first >second
0 equals
-1 second>first

>>74
it does not mean it is correct.

any way, I am done with this bullshit. enjoy your life

>>77
And standard qsort comparator function takes const void *.

>>78
I don't write inline version unless i need the return value from the macro.
printints(array) does not return a value, so it can be written as ;printints(array); to avoid typing extra ;; like
printints(array) puts("STD END MAIN");