implement 25% of #297

Author: pachadotdev

cpp11test/src/test-doubles.cpp

@@ -5,6 +5,7 @@
 #include "cpp11/integers.hpp"
 #include "cpp11/sexp.hpp"
 #include "cpp11/strings.hpp"
+#include "cpp11/logicals.hpp"
 
 #include <testthat.h>
 
@@ -454,6 +455,22 @@ context("doubles-C++") {
     expect_true(!cpp11::is_na(na2[1]));
   }
 
+  test_that("as_doubles(logicals)") {
+    cpp11::writable::logicals y;
+    
+    for (int i = 0; i < 4; i++) {
+      y.push_back(i % 2 == 0);
+    }
+
+    cpp11::doubles i(cpp11::as_doubles(y));
+
+    expect_true(i[0] == 1.0);
+    expect_true(i[1] == 0.0);
+    expect_true(i[2] == 1.0);
+    expect_true(i[3] == 0.0);
+    expect_true(cpp11::detail::r_typeof(i) == REALSXP);
+  }
+
   test_that("doubles operator[] and at") {
     cpp11::doubles x(Rf_allocVector(REALSXP, 2));
     REAL(x)[0] = 1;

inst/include/cpp11/doubles.hpp

@@ -87,6 +87,15 @@ inline doubles as_doubles(SEXP x) {
     return ret;
   }
 
+  else if (detail::r_typeof(x) == LGLSXP) {
+    size_t len = Rf_xlength(x);
+    writable::doubles ret(len);
+    for (size_t i = 0; i < len; ++i) {
+      ret[i] = LOGICAL(x)[i] == NA_LOGICAL ? NA_REAL : static_cast<double>(LOGICAL(x)[i]);
+    }
+    return ret;
+  }
+
   throw type_error(REALSXP, detail::r_typeof(x));
 }