ErrorState Class Reference

#include </opt/build/repo/nap/utility/src/utility/errorstate.h>

Public Member Functions
template<typename T >
bool	check (bool successCondition, T &&errorMessage)
template<typename... Args>
bool	check (bool successCondition, const char *format, Args &&... args)
template<typename T >
void	fail (T &&errorMessage)
template<typename... Args>
void	fail (const char *format, Args &&... args)
const std::string	toString () const
bool	hasErrors () const

Description

ErrorState is a class that can be used to maintain an error state over (nested) function calls. It's useful to be able to return detailed error information from somewhere deep down the stack. It's kind of a poor-man's exception handling in that regard.

Member Function Documentation

check() [1/2]

bool check	(	bool	successCondition,
		const char *	format,
		Args &&...	args
	)

Same as non-templated check(), but allows for easy formatting of error messages.

if (!errorState.check(file != nullptr, "Unable to load file: %s", file.c_str()))
   return false;

Parameters

successCondition	The condition to check (i.e. true/false)
format	The error message that that is formatted
args	the formatting arguments

Returns

Whether the condition evaluated to true (i.e. success) or not

check() [2/2]

bool check	(	bool	successCondition,
		T &&	errorMessage
	)

Check whether the specified condition evaluates to true and adds an error message to the state if not. Often checks are performed on initialization to ensure the resource is valid, for example:

if (!errorState.check(scene != nullptr, "Unable to load scene"))
   return false;

Parameters

successCondition	The condition to check (i.e. true/false)
errorMessage	The error message that belongs to the 'fail' state

Returns

Whether the condition evaluated to true (i.e. success) or not

fail() [1/2]

void fail	(	const char *	format,
		Args &&...	args
	)

Same as non-templated fail(), but allows for easy formatting of error messages

error.fail("unable to read file: %s", file.c_str());
return false;

Parameters

format	the error message that is formatted
args	the format arguments

fail() [2/2]

void fail

(

T &&

errorMessage

)

Add a failure message to the stack. Useful in situations where you already know that you've failed, in which case the check() function is redundant.

error.fail("missing data");
return false;

Parameters

errorMessage

The error message, can be a string literal, std::string etc.

hasErrors()

bool hasErrors

(

)

const

Returns

True if there are any errors, false when everything is okay.

toString()

const std::string toString

(

)

const

Format the error state of this object into a human-readable message

Returns

The full error message