Run Rust from Perl (and from C)

make_c_run_rust.sh

set -e
cat > prime.rs <<EOF
#[no_mangle]
pub extern "C" fn is_prime(n: u64) -> bool {
    if n <= 1 {
        return false;
    }
    // check if even
    if n % 2 == 0 {
        return n == 2;
    }
    if n == 9 {
        return false;
    }

    true
}
EOF
rustc prime.rs -O --crate-type cdylib
export LD_LIBRARY_PATH=.
cat > main.c <<EOF
#include <stdio.h>

extern int is_prime(unsigned int n);

int main() {
  unsigned int n;

  for (n = 0; n < 10; n++) {
    printf("%d %s prime\n", n, is_prime(n) ? "is" : "is not");
  }
  return 0;
}
EOF
gcc main.c -L. -lprime
./a.out

cat >run_prime.pl <<EOF
use v5.36;
use FFI::Platypus 2.00;
use FFI::CheckLib qw( find_lib_or_die );
use File::Basename qw( dirname );

my \$ffi = FFI::Platypus->new( api => 2, lib => './libprime.so' );
\$ffi->attach( is_prime => ['int'] => 'bool' );

say "\n\nHi I'm perl";
say is_prime(7) ? "7 is prime" : "7 is not prime";
say is_prime(8) ? "8 is prime" : "8 is not prime";
say "done that 2";
EOF
perl run_prime.pl