source: doc/theses/mike_brooks_MMath/programs/hello-array.cfa@ a885357

#include <fstream.hfa>
#include <stdlib.hfa>
#include <array.hfa> // learned has to come afer stdlib, which uses the word tag

// Usage:
// ./a.out 5
// example does an unchecked reference to argv[1]


forall( [N] ) // array bound
array(bool, N) & f( array(float, N) & a, array(float, N) & b ) {
        array(bool, N) & ret = *alloc(); // sizeof used by alloc
        for( i; N ) {
                ret[i] = 0.005 > 2 * (abs(a[i] - b[i])) / (abs(a[i]) + abs(b[i]));
        }
        return ret;
}










// TODO: standardize argv

int main( int argc, char * argv[] ) {
        int n = ato( argv[1] );
        array(float, n) a, b; // VLA
        for ( i; n ) {
                a[i] = 3.14 / (i + 1);
                b[i] = a[i] + 0.005 ;
        }
        array(bool, n) & result = f( a, b ); // call
        sout | "result: " | nonl;
        for ( i; n )
                sout | result[i] | nonl;
        sout | nl;
        free( &result ); // free returned storage
}
/*
$\$$ ./a.out 5
result: true true true false false
$\$$ ./a.out 7
result: true true true false false false false
*/

void fred() {
        array(float, 10) a;
        array(float, 20) b;
        f( a, a );
        f( b, b );
        f( a, b );
}

#ifdef SHOWERR1
forall( [M], [N] )
void bad( array(float, M) &a, array(float, N) &b ) {
        f( a, a ); // ok
        f( b, b ); // ok
        f( a, b ); // error
}
#endif



forall( [M], [N] )
void bad_fixed( array(float, M) & a, array(float, N) & b ) {
        if ( M == N ) {
                f( a, (array(float, M) &)b ); // cast b to matching type
        }
}