erase() [2/4]

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, class BinaryType = std::vector<std::uint8_t>>

size_type nlohmann::basic_json< ObjectType, ArrayType, StringType, BooleanType, NumberIntegerType, NumberUnsignedType, NumberFloatType, AllocatorType, JSONSerializer, BinaryType >::erase ( const typename object_t::key_type &  key )

inline

remove element from a JSON object given a key

Removes elements from a JSON object with the key value key.

Parameters

[in]

key

value of the elements to remove

Returns

Number of elements removed. If ObjectType is the default std::map type, the return value will always be 0 (key was not found) or 1 (key was found).

Postcondition

References and iterators to the erased elements are invalidated. Other references and iterators are not affected.

Exceptions

type_error.307

when called on a type other than JSON object; example: "cannot use erase() with null"

@complexity log(size()) + count(key)

@liveexample{The example shows the effect of erase().,erase__key_type}

See also

see erase(IteratorType) – removes the element at a given position

see erase(IteratorType, IteratorType) – removes the elements in the given range

see erase(const size_type) – removes the element from an array at the given index

Since

version 1.0.0

Definition at line 22134 of file json.hpp.

    {
        // this erase only works for objects
        if (JSON_HEDLEY_LIKELY(is_object()))
        {
            return m_value.object->erase(key);
        }
 
        JSON_THROW(type_error::create(307, "cannot use erase() with " + std::string(type_name()), *this));
    }