// The `is_defined` guard prevents redefining functions
#[if(!is_defined("STR")) {
    const STR = 1;

    fn strlen(str: &char) -> num {
        for (let i=0; str[i] != 0; i=i+1) {}
        return i
    }
    
    fn strcpy(dst: &char, src: &char) {
        for (let i=0; src[i] != 0; i=i+1) {
            dst[i] = src[i];
        }
        dst[i] = 0;
    }
    
    fn strcat(dst: &char, src: &char) {
        let offset = strlen(dst);
        for (let i=0; src[i] != 0; i=i+1) {
            dst[offset+i] = src[i];
        }
        dst[offset+i] = 0;
    }
}]