diff --git a/include/nlohmann/detail/input/parser.hpp b/include/nlohmann/detail/input/parser.hpp
index 8346cd4b..32f2be88 100644
--- a/include/nlohmann/detail/input/parser.hpp
+++ b/include/nlohmann/detail/input/parser.hpp
@@ -164,6 +164,8 @@ class parser
{
// never parse after a parse error was detected
assert(not errored);
+ // this function is only called when a callback is given
+ assert(callback);
// start with a discarded value
if (not result.is_discarded())
@@ -178,12 +180,9 @@ class parser
{
if (keep)
{
- if (callback)
- {
- keep = callback(depth++, parse_event_t::object_start, result);
- }
+ keep = callback(depth++, parse_event_t::object_start, result);
- if (not callback or keep)
+ if (keep)
{
// explicitly set result to object to cope with {}
result.m_type = value_t::object;
@@ -197,7 +196,7 @@ class parser
// closing } -> we are done
if (last_token == token_type::end_object)
{
- if (keep and callback and not callback(--depth, parse_event_t::object_end, result))
+ if (keep and not callback(--depth, parse_event_t::object_end, result))
{
result.m_value.destroy(result.m_type);
result.m_type = value_t::discarded;
@@ -220,15 +219,8 @@ class parser
bool keep_tag = false;
if (keep)
{
- if (callback)
- {
- BasicJsonType k(key);
- keep_tag = callback(depth, parse_event_t::key, k);
- }
- else
- {
- keep_tag = true;
- }
+ BasicJsonType k(key);
+ keep_tag = callback(depth, parse_event_t::key, k);
}
// parse separator (:)
@@ -270,7 +262,7 @@ class parser
break;
}
- if (keep and callback and not callback(--depth, parse_event_t::object_end, result))
+ if (keep and not callback(--depth, parse_event_t::object_end, result))
{
result.m_value.destroy(result.m_type);
result.m_type = value_t::discarded;
@@ -282,12 +274,9 @@ class parser
{
if (keep)
{
- if (callback)
- {
- keep = callback(depth++, parse_event_t::array_start, result);
- }
+ keep = callback(depth++, parse_event_t::array_start, result);
- if (not callback or keep)
+ if (keep)
{
// explicitly set result to array to cope with []
result.m_type = value_t::array;
@@ -301,7 +290,7 @@ class parser
// closing ] -> we are done
if (last_token == token_type::end_array)
{
- if (callback and not callback(--depth, parse_event_t::array_end, result))
+ if (not callback(--depth, parse_event_t::array_end, result))
{
result.m_value.destroy(result.m_type);
result.m_type = value_t::discarded;
@@ -344,7 +333,7 @@ class parser
break;
}
- if (keep and callback and not callback(--depth, parse_event_t::array_end, result))
+ if (keep and not callback(--depth, parse_event_t::array_end, result))
{
result.m_value.destroy(result.m_type);
result.m_type = value_t::discarded;
@@ -432,7 +421,7 @@ class parser
}
}
- if (keep and callback and not callback(depth, parse_event_t::value, result))
+ if (keep and not callback(depth, parse_event_t::value, result))
{
result.m_value.destroy(result.m_type);
result.m_type = value_t::discarded;
diff --git a/single_include/nlohmann/json.hpp b/single_include/nlohmann/json.hpp
index cdd55475..666150d9 100644
--- a/single_include/nlohmann/json.hpp
+++ b/single_include/nlohmann/json.hpp
@@ -3641,6 +3641,8 @@ class parser
{
// never parse after a parse error was detected
assert(not errored);
+ // this function is only called when a callback is given
+ assert(callback);
// start with a discarded value
if (not result.is_discarded())
@@ -3655,12 +3657,9 @@ class parser
{
if (keep)
{
- if (callback)
- {
- keep = callback(depth++, parse_event_t::object_start, result);
- }
+ keep = callback(depth++, parse_event_t::object_start, result);
- if (not callback or keep)
+ if (keep)
{
// explicitly set result to object to cope with {}
result.m_type = value_t::object;
@@ -3674,7 +3673,7 @@ class parser
// closing } -> we are done
if (last_token == token_type::end_object)
{
- if (keep and callback and not callback(--depth, parse_event_t::object_end, result))
+ if (keep and not callback(--depth, parse_event_t::object_end, result))
{
result.m_value.destroy(result.m_type);
result.m_type = value_t::discarded;
@@ -3697,15 +3696,8 @@ class parser
bool keep_tag = false;
if (keep)
{
- if (callback)
- {
- BasicJsonType k(key);
- keep_tag = callback(depth, parse_event_t::key, k);
- }
- else
- {
- keep_tag = true;
- }
+ BasicJsonType k(key);
+ keep_tag = callback(depth, parse_event_t::key, k);
}
// parse separator (:)
@@ -3747,7 +3739,7 @@ class parser
break;
}
- if (keep and callback and not callback(--depth, parse_event_t::object_end, result))
+ if (keep and not callback(--depth, parse_event_t::object_end, result))
{
result.m_value.destroy(result.m_type);
result.m_type = value_t::discarded;
@@ -3759,12 +3751,9 @@ class parser
{
if (keep)
{
- if (callback)
- {
- keep = callback(depth++, parse_event_t::array_start, result);
- }
+ keep = callback(depth++, parse_event_t::array_start, result);
- if (not callback or keep)
+ if (keep)
{
// explicitly set result to array to cope with []
result.m_type = value_t::array;
@@ -3778,7 +3767,7 @@ class parser
// closing ] -> we are done
if (last_token == token_type::end_array)
{
- if (callback and not callback(--depth, parse_event_t::array_end, result))
+ if (not callback(--depth, parse_event_t::array_end, result))
{
result.m_value.destroy(result.m_type);
result.m_type = value_t::discarded;
@@ -3821,7 +3810,7 @@ class parser
break;
}
- if (keep and callback and not callback(--depth, parse_event_t::array_end, result))
+ if (keep and not callback(--depth, parse_event_t::array_end, result))
{
result.m_value.destroy(result.m_type);
result.m_type = value_t::discarded;
@@ -3909,7 +3898,7 @@ class parser
}
}
- if (keep and callback and not callback(depth, parse_event_t::value, result))
+ if (keep and not callback(depth, parse_event_t::value, result))
{
result.m_value.destroy(result.m_type);
result.m_type = value_t::discarded;
diff --git a/test/src/unit-class_parser.cpp b/test/src/unit-class_parser.cpp
index 39753d68..d84148eb 100644
--- a/test/src/unit-class_parser.cpp
+++ b/test/src/unit-class_parser.cpp
@@ -176,7 +176,18 @@ bool accept_helper(const std::string& s)
CHECK_NOTHROW(json::sax_parse(s, &el));
CHECK(json::parser(nlohmann::detail::input_adapter(s)).accept(false) == not el.errored);
- // 5. return result
+ // 5. parse with simple callback
+ json::parser_callback_t cb = [](int, json::parse_event_t, json&)
+ {
+ return true;
+ };
+ json j_cb = json::parse(s, cb, false);
+ const bool ok_noexcept_cb = not j_cb.is_discarded();
+
+ // 6. check if this approach came to the same result
+ CHECK(ok_noexcept == ok_noexcept_cb);
+
+ // 7. return result
return ok_accept;
}