Add print wrappers for debugging

Author: lionel-

crates/harp/src/utils.rs

@@ -649,3 +649,16 @@ pub fn push_rds(x: SEXP, path: &str, context: &str) {
     // This is meant for internal use so report errors loudly
     res.unwrap();
 }
+
+pub fn r_print(x: impl Into<SEXP>) {
+    unsafe {
+        Rf_PrintValue(x.into());
+    }
+}
+
+pub fn r_printf(x: &str) {
+    let c_str = std::ffi::CString::new(x).unwrap();
+    unsafe {
+        libr::Rprintf(c_str.as_ptr());
+    }
+}

crates/libr/src/r.rs

@@ -355,6 +355,8 @@ functions_variadic::generate! {
     pub fn Rf_error(arg1: *const std::ffi::c_char, ...) -> !;
 
     pub fn Rf_errorcall(arg1: SEXP, arg2: *const std::ffi::c_char, ...) -> !;
+
+    pub fn Rprintf(x: *const std::ffi::c_char, ...);
 }
 
 constant_globals::generate! {