sdk: Samples should use idomatic C++ (#93)

Author: malone-at-work

villagesql/sdk/include/villagesql/extension.h

@@ -29,13 +29,12 @@
 // Create a .cc file for your extension:
 //
 //   #include <villagesql/extension.h>
+//   using namespace villagesql;
 //
 //   // Implement your function
-//   void add_impl(vef_context_t* ctx,
-//                 vef_invalue_t* a, vef_invalue_t* b,
-//                 vef_vdf_result_t* result) {
-//     result->int_value = a->int_value + b->int_value;
-//     result->type = VEF_RESULT_VALUE;
+//   void add_impl(IntArg a, IntArg b, IntResult out) {
+//     if (a.is_null() || b.is_null()) { out.set_null(); return; }
+//     out.set(a.value() + b.value());
 //   }
 //
 //   // Register the extension with inline function definitions
@@ -79,7 +78,7 @@
 //     out.set_length(src.size());
 //   }
 //
-// DEFINING FUNCTIONS (deprecated, will be removed)
+// DEFINING FUNCTIONS
 // ------------------
 //
 // Functions are defined using make_func<&impl>("name") and chained builder
@@ -173,6 +172,7 @@
 //
 //   #include <villagesql/extension.h>
 //   #include <cstring>
+//   using namespace villagesql;
 //
 //   static const size_t kBytearrayLen = 8;
 //   constexpr const char* BYTEARRAY = "bytearray";
@@ -206,17 +206,17 @@
 //   }
 //
 //   // ROT13: apply ROT13 cipher to ASCII letters in a bytearray
-//   void rot13_impl(vef_context_t* ctx,
-//                   vef_invalue_t* input, vef_vdf_result_t* result) {
-//     if (input->is_null) { result->type = VEF_RESULT_NULL; return; }
+//   void rot13_impl(BinaryArg input, BinaryResult out) {
+//     if (input.is_null()) { out.set_null(); return; }
+//     auto src = input.value();   // villagesql::Span<const unsigned char>
+//     auto dst = out.buffer();    // villagesql::Span<unsigned char>
 //     for (size_t i = 0; i < kBytearrayLen; i++) {
-//       unsigned char c = input->bin_value[i];
+//       unsigned char c = src[i];
 //       if (c >= 'A' && c <= 'Z') c = 'A' + ((c - 'A' + 13) % 26);
 //       else if (c >= 'a' && c <= 'z') c = 'a' + ((c - 'a' + 13) % 26);
-//       result->bin_buf[i] = c;
+//       dst[i] = c;
 //     }
-//     result->type = VEF_RESULT_VALUE;
-//     result->actual_len = kBytearrayLen;
+//     out.set_length(kBytearrayLen);
 //   }
 //
 //   // Register everything inline

villagesql/sdk/include/villagesql/func_types.h

@@ -31,13 +31,13 @@
 //   StringResult / BinaryResult: write into buffer(), then call set_length().
 //
 // Example - integer add:
-//   void add(vef_context_t*, IntArg a, IntArg b, IntResult out) {
+//   void add(IntArg a, IntArg b, IntResult out) {
 //     if (a.is_null() || b.is_null()) { out.set_null(); return; }
 //     out.set(a.value() + b.value());
 //   }
 //
 // Example - binary transform (ROT13 on a fixed-size BYTEARRAY):
-//   void rot13(vef_context_t*, BinaryArg in, BinaryResult out) {
+//   void rot13(BinaryArg in, BinaryResult out) {
 //     if (in.is_null()) { out.set_null(); return; }
 //     auto src = in.value();          // villagesql::Span<const unsigned char>
 //     auto dst = out.buffer();        // villagesql::Span<unsigned char>

villagesql/sdk/template/src/extension.cc

@@ -20,18 +20,15 @@
 // See the extension.h header for full documentation.
 
 #include <villagesql/extension.h>
+using namespace villagesql;
 
 // Example function: adds two integers
-// INT parameters are passed natively in the int_value field.
-void add_impl(vef_context_t *ctx, vef_invalue_t *a, vef_invalue_t *b,
-              vef_vdf_result_t *result) {
-  if (a->is_null || b->is_null) {
-    result->type = VEF_RESULT_NULL;
+void add_impl(IntArg a, IntArg b, IntResult out) {
+  if (a.is_null() || b.is_null()) {
+    out.set_null();
     return;
   }
-
-  result->int_value = a->int_value + b->int_value;
-  result->type = VEF_RESULT_VALUE;
+  out.set(a.value() + b.value());
 }
 
 // Register the extension