=proto
const char *duk_safe_to_string(duk_context *ctx, duk_idx_t index);

=stack
[ ... val! ... ] -> [ ... ToString(val)! ... ]

=summary
<p>Like <code><a href="#duk_to_string">duk_to_string()</a></code> but if
the initial string coercion fails, the error value is coerced to a string.
If that also fails, a fixed error string is returned.</p>

<p>The caller can safely use this function to coerce a value to a string,
which is useful in C code to print out a return value safely with
<code>printf()</code>.  The only uncaught errors possible are out-of-memory
and other internal errors which trigger fatal error handling anyway.</p>

=example
/* Coercion causes error. */
duk_eval_string(ctx, "({ toString: function () { throw new Error('toString error'); } })");
printf("coerced string: %s\n", duk_safe_to_string(ctx, -1));  /* -> "Error: toString error" */
duk_pop(ctx);

/* Coercion causes error, and the error itself cannot be string coerced. */
duk_eval_string(ctx, "({ toString: function () { var e = new Error('cannot string coerce me');"
                     "                           e.toString = function () { throw new Error('coercion error'); };"
                     "                           throw e; } })");
printf("coerced string: %s\n", duk_safe_to_string(ctx, -1));  /* -> "Error" */
duk_pop(ctx);

=tags
stack
string
protected

=seealso
duk_to_string