cppfig::Value Class Reference

A self-contained, recursive value type for configuration data. More...

#include <value.h>

Public Types
using	ObjectType = std::map< std::string, Value, std::less<> >
	Ordered map of string keys to Value children.
using	ArrayType = std::vector< Value >
	Ordered sequence of Value elements.

Public Member Functions
	Value ()
	Constructs a null value.
	Value (std::nullptr_t)
	Constructs a null value.
	Value (bool b)
	Constructs a boolean value.
	Value (int i)
	Constructs an integer value from int.
	Value (std::int64_t i)
	Constructs an integer value.
	Value (double d)
	Constructs a double value.
	Value (float f)
	Constructs a double value from float.
	Value (const char *s)
	Constructs a string value from a C string.
	Value (std::string s)
	Constructs a string value.
	Value (std::string_view s)
	Constructs a string value from string_view.
	Value (const Value &other)
	Deep-copies the value (recursive for objects / arrays).
auto	operator= (const Value &other) -> Value &
	Deep-copy assignment.
	Value (Value &&) noexcept=default
	Move constructor (default, transfers ownership).
auto	operator= (Value &&) noexcept -> Value &=default
	Move assignment (default).
	~Value ()=default
	Destructor (default, unique_ptr handles cleanup).
auto	IsNull () const -> bool
	Returns true if this value is null.
auto	IsBoolean () const -> bool
	Returns true if this value is a boolean.
auto	IsInteger () const -> bool
	Returns true if this value is an integer.
auto	IsDouble () const -> bool
	Returns true if this value is a double.
auto	IsNumber () const -> bool
	Returns true if this value is any numeric type (integer or double).
auto	IsString () const -> bool
	Returns true if this value is a string.
auto	IsObject () const -> bool
	Returns true if this value is an object (key-value map).
auto	IsArray () const -> bool
	Returns true if this value is an array.
template<typename T >
auto	Fits () const -> bool
	Returns true if the stored value is representable as T.
template<typename T >
auto	Get () const -> T
	Extracts the stored value as the requested type.
auto	TryToText () const -> std::optional< std::string >
	Renders a scalar value as text, or nullopt for objects/arrays.
template<typename T >
auto	TryGet () const -> std::optional< T >
	Extracts the stored value as T, or nullopt if it is not one.
auto	Contains (std::string_view key) const -> bool
	Checks whether the given key exists in an object value.
auto	operator[] (const std::string &key) -> Value &
	Accesses or creates a child by key, promoting null → object.
auto	operator[] (const std::string &key) const -> const Value &
	Read-only access to a child by key (returns static null for missing keys).
auto	Items () const -> const ObjectType &
	Returns const reference to the object entries.
auto	Items () -> ObjectType &
	Returns mutable reference to the object entries, promoting null → object.
auto	Elements () const -> const ArrayType &
	Returns const reference to the array elements.
auto	Elements () -> ArrayType &
	Returns mutable reference to the array elements, promoting null → array.
auto	GetAtPath (std::string_view path) const -> StatusOr< Value >
	Gets a value at a dot-separated path.
void	SetAtPath (std::string_view path, const Value &value)
	Sets a value at a dot-separated path, creating intermediate objects.
auto	HasPath (std::string_view path) const -> bool
	Checks if a path exists in the data.
auto	Dump (int indent=0) const -> std::string
	Produces a JSON-like string representation.
auto	operator== (const Value &other) const -> bool
	Value equality (deep comparison for objects/arrays).
auto	operator!= (const Value &other) const -> bool
	Value inequality.

Static Public Member Functions
static auto	Object () -> Value
	Creates an empty object value.
static auto	Array () -> Value
	Creates an empty array value.
static auto	SplitPath (std::string_view path) -> std::vector< std::string >
	Splits a dot-separated path into its segments.
static auto	Merge (const Value &base, const Value &overlay) -> Value
	Deep-merges two object values; overlay takes precedence.

Detailed Description

A self-contained, recursive value type for configuration data.

This type replaces external JSON dependencies in the core library. It supports: null, bool, int64, double, string, object (map), and array.

Objects use std::map with transparent comparison for efficient std::string_view lookups. Recursive containers are heap-allocated via std::unique_ptr to keep the variant's inline size small; a custom copy constructor deep-copies them, so the pointer is never actually shared and the type has plain value semantics.

Member Typedef Documentation

ArrayType

using cppfig::Value::ArrayType = std::vector<Value>

Ordered sequence of Value elements.

ObjectType

using cppfig::Value::ObjectType = std::map<std::string, Value, std::less<> >

Ordered map of string keys to Value children.

Constructor & Destructor Documentation

Value() [1/12]

cppfig::Value::Value ( )

inline

Constructs a null value.

Value() [2/12]

cppfig::Value::Value ( std::nullptr_t  )

inline

Constructs a null value.

Value() [3/12]

cppfig::Value::Value ( bool  b )

inline

Constructs a boolean value.

Value() [4/12]

cppfig::Value::Value ( int  i )

inline

Constructs an integer value from int.

Value() [5/12]

cppfig::Value::Value ( std::int64_t  i )

inline

Constructs an integer value.

Value() [6/12]

cppfig::Value::Value ( double  d )

inline

Constructs a double value.

Value() [7/12]

cppfig::Value::Value ( float  f )

inline

Constructs a double value from float.

Value() [8/12]

cppfig::Value::Value ( const char *  s )

inline

Constructs a string value from a C string.

Value() [9/12]

cppfig::Value::Value ( std::string  s )

inline

Constructs a string value.

Value() [10/12]

cppfig::Value::Value ( std::string_view  s )

inline

Constructs a string value from string_view.

Value() [11/12]

cppfig::Value::Value ( const Value &  other )

inline

Deep-copies the value (recursive for objects / arrays).

Value() [12/12]

cppfig::Value::Value ( Value &&  )

defaultnoexcept

Move constructor (default, transfers ownership).

~Value()

cppfig::Value::~Value ( )

default

Destructor (default, unique_ptr handles cleanup).

Member Function Documentation

Array()

static auto cppfig::Value::Array ( ) -> Value

inlinestatic

Creates an empty array value.

Contains()

auto cppfig::Value::Contains ( std::string_view  key ) const -> bool

inline

Checks whether the given key exists in an object value.

Dump()

auto cppfig::Value::Dump ( int  indent = 0 ) const -> std::string

inline

Produces a JSON-like string representation.

Parameters

indent

Number of spaces per indentation level (0 = compact).

Elements() [1/2]

auto cppfig::Value::Elements ( ) -> ArrayType&

inline

Returns mutable reference to the array elements, promoting null → array.

Elements() [2/2]

auto cppfig::Value::Elements ( ) const -> const ArrayType&

inline

Returns const reference to the array elements.

Fits()

template<typename T >

auto cppfig::Value::Fits ( ) const -> bool

inline

Returns true if the stored value is representable as T.

Reports false both when the stored alternative is the wrong kind and when it is numerically out of range for T (an int64 too large for an int, a double too large for a float).

Get()

template<typename T >

auto cppfig::Value::Get ( ) const -> T

inline

Extracts the stored value as the requested type.

Supported types: bool, int, std::int64_t, double, float, std::string. Integer↔double conversions are performed with static_cast when the underlying storage differs from the requested type.

Exceptions

std::bad_variant_access	if the stored value is of another kind.
std::out_of_range	if the stored value does not fit in T. Discarding the high bits of an out-of-range value would turn a plainly wrong configuration into a plausible-looking one, so callers that cannot guarantee the range should check Fits first (ConfigTraits does).

GetAtPath()

auto cppfig::Value::GetAtPath ( std::string_view  path ) const -> StatusOr<Value>

inline

Gets a value at a dot-separated path.

Returns

The value at the path, or a NotFound error if the path is ill-formed or does not resolve.

HasPath()

auto cppfig::Value::HasPath ( std::string_view  path ) const -> bool

inline

Checks if a path exists in the data.

IsArray()

auto cppfig::Value::IsArray ( ) const -> bool

inline

Returns true if this value is an array.

IsBoolean()

auto cppfig::Value::IsBoolean ( ) const -> bool

inline

Returns true if this value is a boolean.

IsDouble()

auto cppfig::Value::IsDouble ( ) const -> bool

inline

Returns true if this value is a double.

IsInteger()

auto cppfig::Value::IsInteger ( ) const -> bool

inline

Returns true if this value is an integer.

IsNull()

auto cppfig::Value::IsNull ( ) const -> bool

inline

Returns true if this value is null.

IsNumber()

auto cppfig::Value::IsNumber ( ) const -> bool

inline

Returns true if this value is any numeric type (integer or double).

IsObject()

auto cppfig::Value::IsObject ( ) const -> bool

inline

Returns true if this value is an object (key-value map).

IsString()

auto cppfig::Value::IsString ( ) const -> bool

inline

Returns true if this value is a string.

Items() [1/2]

auto cppfig::Value::Items ( ) -> ObjectType&

inline

Returns mutable reference to the object entries, promoting null → object.

Items() [2/2]

auto cppfig::Value::Items ( ) const -> const ObjectType&

inline

Returns const reference to the object entries.

Merge()

static auto cppfig::Value::Merge ( const Value &  base, const Value &  overlay  ) -> Value

inlinestatic

Deep-merges two object values; overlay takes precedence.

• Objects are merged recursively.
• Arrays and primitives from overlay replace base entirely.

Object()

static auto cppfig::Value::Object ( ) -> Value

inlinestatic

Creates an empty object value.

operator!=()

auto cppfig::Value::operator!= ( const Value &  other ) const -> bool

inline

Value inequality.

operator=() [1/2]

auto cppfig::Value::operator= ( const Value &  other ) -> Value&

inline

Deep-copy assignment.

operator=() [2/2]

auto cppfig::Value::operator= ( Value &&  ) -> Value &=default

defaultnoexcept

Move assignment (default).

operator==()

auto cppfig::Value::operator== ( const Value &  other ) const -> bool

inline

Value equality (deep comparison for objects/arrays).

operator[]() [1/2]

auto cppfig::Value::operator[] ( const std::string &  key ) -> Value&

inline

Accesses or creates a child by key, promoting null → object.

operator[]() [2/2]

auto cppfig::Value::operator[] ( const std::string &  key ) const -> const Value&

inline

Read-only access to a child by key (returns static null for missing keys).

SetAtPath()

void cppfig::Value::SetAtPath ( std::string_view  path, const Value &  value  )

inline

Sets a value at a dot-separated path, creating intermediate objects.

Ill-formed paths are ignored; use SplitPath to validate a path before calling if the caller needs to report the failure.

SplitPath()

static auto cppfig::Value::SplitPath ( std::string_view  path ) -> std::vector<std::string>

inlinestatic

Splits a dot-separated path into its segments.

A path is well-formed only if it is non-empty and every segment between the dots is non-empty. Ill-formed paths ("", "a.", ".a", "a..b") yield an empty result and are rejected by the path accessors rather than silently creating blank keys.

TryGet()

template<typename T >

auto cppfig::Value::TryGet ( ) const -> std::optional<T>

inline

Extracts the stored value as T, or nullopt if it is not one.

The library's error model is Status and std::optional everywhere else; this is the accessor to reach for in ConfigTraits specialisations and anywhere the stored kind is not already known, so a type mismatch does not have to be handled as an exception.

TryToText()

auto cppfig::Value::TryToText ( ) const -> std::optional<std::string>

inline

Renders a scalar value as text, or nullopt for objects/arrays.

Flat formats store every leaf as text, so this is the bridge back to ConfigTraits::FromString when a parsed leaf has to be reinterpreted as the type the schema declares.

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The documentation for this class was generated from the following file:

• src/cppfig/value.h