#include <userver/formats/common/conversion_stack.hpp>
Used in the implementation of functions that convert between different formats, e.g. formats::yaml::Value to formats::json::Value, etc.
Does not use recursion, so stack overflow will never happen with deeply nested or wide objects or arrays.
ValueFrom | the Value type, FROM which we convert, e.g. formats::yaml::Value |
ValueToBuilder | the ValueBuilder type, TO which we convert, e.g. formats::json::ValueBuilder |
How to build the conversion function:
ValueFrom
!IsParsed
:GetNextFrom
ValueFrom
GetParsed
See the implementation of PerformMinimalFormatConversion as an example.
Definition at line 47 of file conversion_stack.hpp.
Public Member Functions | |
ConversionStack (ValueFrom value) | |
Start the conversion from value . | |
ConversionStack (ConversionStack &&)=delete | |
ConversionStack & | operator= (ConversionStack &&)=delete |
bool | IsParsed () const |
Check whether the whole source ValueFrom has been parsed. | |
ValueToBuilder && | GetParsed () && |
Get the parsing result, precondition: IsParsed() . | |
const ValueFrom & | GetNextFrom () const |
Get the current sub-ValueFrom to convert. | |
template<typename T > | |
void | CastCurrentPrimitive () |
template<typename T > | |
void | SetCurrent (T &&value) |
void | EnterItems () |
Use for when an object or an array ValueFrom is encountered. | |
|
inlineexplicit |
Start the conversion from value
.
Definition at line 50 of file conversion_stack.hpp.
|
inline |
Use for when it's discovered that the current ValueFrom
type is available and has the same semantics in ValueFrom and ValueToBuilder, e.g. std::int64_t
, std::string
, etc.
Definition at line 81 of file conversion_stack.hpp.
|
inline |
Use for when an object or an array ValueFrom
is encountered.
Definition at line 98 of file conversion_stack.hpp.
|
inline |
Get the current sub-ValueFrom
to convert.
Definition at line 67 of file conversion_stack.hpp.
|
inline |
Get the parsing result, precondition: IsParsed()
.
Definition at line 61 of file conversion_stack.hpp.
|
inline |
Check whether the whole source ValueFrom has been parsed.
Definition at line 58 of file conversion_stack.hpp.
|
inline |
Use for when it's discovered that the current ValueFrom
type is not directly convertible to ValueToBuilder
, but can be converted manually (this might be an inexact conversion). For example, ValueFrom could have a special representation for datetime, and we manually convert it to string using some arbitrary format.
Definition at line 92 of file conversion_stack.hpp.