name: duk_is_c_function

proto: |
  duk_bool_t duk_is_c_function(duk_context *ctx, duk_idx_t index);

stack: |
  [ ... val! ... ]

summary: |
  <p>Returns 1 if value at <code>index</code> is a Function object and is
  assocated with a C function, otherwise returns 0.
  If <code>index</code> is invalid, also returns 0.</p>

  <p>An example of an underlying C function observing the Duktape/C API
  calling convention:</p>
  <pre class="c-code">
  int my_func(duk_context *ctx) {
      /* ... */
  }
  </pre>

example: |
  if (duk_is_c_function(ctx, -3)) {
      /* ... */
  }

tags:
  - stack
  - function

introduced: 1.0.0