Function rb_String 

pub unsafe extern "C" fn rb_String(val: VALUE) -> VALUE

This is the logic behind Kernel#String. Arguments are converted by first trying #to_str, then #to_s.

@param[in] val An object to convert. @exception rb_eTypeError No conversion defined. @return An instance of ::rb_cString.

Generated by rb-sys for Ruby mri-x86_64-linux-gnu-3.2.3