llvm::json::ObjectMapper Class Reference

Helper for mapping JSON objects onto protocol structs. More...

#include "llvm/Support/JSON.h"

Public Member Functions
	ObjectMapper (const Value &E, Path P)
	If O is not an object, this mapper is invalid and an error is reported.
	operator bool () const
	True if the expression is an object.
template<typename T >
bool	map (StringLiteral Prop, T &Out)
	Maps a property to a field.
template<typename T >
bool	map (StringLiteral Prop, std::optional< T > &Out)
	Maps a property to a field, if it exists.
template<typename T >
bool	mapOptional (StringLiteral Prop, T &Out)
	Maps a property to a field, if it exists.

Detailed Description

Helper for mapping JSON objects onto protocol structs.

Example:

bool fromJSON(const Value &E, MyStruct &R, Path P) {
  ObjectMapper O(E, P);
  // When returning false, error details were already reported.
  return O && O.map("mandatory_field", R.MandatoryField) &&
      O.mapOptional("optional_field", R.OptionalField);
}

Definition at line 827 of file JSON.h.

Constructor & Destructor Documentation

ObjectMapper()

llvm::json::ObjectMapper::ObjectMapper ( const Value &  E, Path  P  )

inline

If O is not an object, this mapper is invalid and an error is reported.

Definition at line 830 of file JSON.h.

References P.

Member Function Documentation

map() [1/2]

template<typename T >

bool llvm::json::ObjectMapper::map ( StringLiteral  Prop, std::optional< T > &  Out  )

inline

Maps a property to a field, if it exists.

If the property exists and is invalid, reports an error. (Optional requires special handling, because missing keys are OK).

Definition at line 852 of file JSON.h.

References assert(), E, llvm::json::Path::field(), llvm::json::fromJSON(), and llvm::json::Object::get().

map() [2/2]

template<typename T >

bool llvm::json::ObjectMapper::map ( StringLiteral  Prop, T &  Out  )

inline

Maps a property to a field.

If the property is missing or invalid, reports an error.

Definition at line 841 of file JSON.h.

References assert(), E, llvm::json::Path::field(), llvm::json::fromJSON(), llvm::json::Object::get(), and llvm::json::Path::report().

Referenced by llvm::getTensorSpecFromJSON().

mapOptional()

template<typename T >

bool llvm::json::ObjectMapper::mapOptional ( StringLiteral  Prop, T &  Out  )

inline

Maps a property to a field, if it exists.

If the property exists and is invalid, reports an error. If the property does not exist, Out is unchanged.

Definition at line 863 of file JSON.h.

References assert(), E, llvm::json::Path::field(), llvm::json::fromJSON(), and llvm::json::Object::get().

operator bool()

llvm::json::ObjectMapper::operator bool ( ) const

inline

True if the expression is an object.

Must be checked before calling map().

Definition at line 837 of file JSON.h.

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

• include/llvm/Support/JSON.h