template<template< typename U, typename V, typename... Args > class ObjectType = std::map, template< typename U, typename... Args > class ArrayType = std::vector, class StringType = std::string, class BooleanType = bool, class NumberIntegerType = std::int64_t, class NumberUnsignedType = std::uint64_t, class NumberFloatType = double, template< typename U > class AllocatorType = std::allocator, template< typename T, typename SFINAE=void > class JSONSerializer = adl_serializer>
template<typename ScalarType , typename std::enable_if< std::is_scalar< ScalarType >::value, int >::type = 0>
comparison: less than Compares whether one JSON value lhs is less than another JSON value rhs according to the following rules:
- If lhs and rhs have the same type, the values are compared using the default
<
operator.
- Integer and floating-point numbers are automatically converted before comparison
- In case lhs and rhs have different types, the values are ignored and the order of the types is considered, see operator<(const value_t, const value_t).
- Parameters
-
[in] | lhs | first JSON value to consider |
[in] | rhs | second JSON value to consider |
- Returns
- whether lhs is less than rhs
- Complexity^^ Linear.
- Exception safety^^ No-throw guarantee: this function never throws exceptions.
- Example^^ The example demonstrates comparing several JSON
- types. ^^
2 #include <nlohmann/json.hpp> 9 json array_1 = {1, 2, 3};
10 json array_2 = {1, 2, 4};
11 json object_1 = {{
"A",
"a"}, {
"B",
"b"}};
12 json object_2 = {{
"B",
"b"}, {
"A",
"a"}};
14 json number_2 = 17.0000000000001L;
15 json string_1 =
"foo";
16 json string_2 =
"bar";
19 std::cout << std::boolalpha;
20 std::cout << array_1 <<
" == " << array_2 <<
" " << (array_1 < array_2) <<
'\n';
21 std::cout << object_1 <<
" == " << object_2 <<
" " << (object_1 < object_2) <<
'\n';
22 std::cout << number_1 <<
" == " << number_2 <<
" " << (number_1 < number_2) <<
'\n';
23 std::cout << string_1 <<
" == " << string_2 <<
" " << (string_1 < string_2) <<
'\n';
basic_json<> json
default JSON class
Output (play with this example online):^^ [1,2,3] == [1,2,4] true
{"A":"a","B":"b"} == {"A":"a","B":"b"} false
17 == 17.0000000000001 true
"foo" == "bar" false
^^ The example code above can be translated withg++ -std=c++11 -Isingle_include doc/examples/operator__less.cpp -o operator__less
- Since
- version 1.0.0
Definition at line 18150 of file json.hpp.