Functions Reference


                    
                    
                    assert(_:error:file:line:)

Performs a traditional C-style assert with an Error.

Declaration

Swift

@inlinable
public func assert(_ condition: @autoclosure () -> Bool,
                   error: Error,
                   file: StaticString = #file,
                   line: UInt = #line)

Parameters

`condition`	The condition to test. `condition` is only evaluated in playgrounds and `-Onone` builds.
`error`	The error that represents the assertion failure when `condition` evaluates to `false`.
`file`	The file name to print with the description of `error` if the assertion fails. The default is the file where `assert(_:error:file:line:)` is called.
`line`	The line number to print along with the description of `error` if the assertion fails. The default is the line number where `assert(_:error:file:line:)` is called.


                    
                    
                    assert(_:_:file:line:)

Performs a traditional C-style assert with an optional message.

Declaration

Swift

@inlinable
public func assert(_ condition: @autoclosure () -> Bool,
                   _ message: @autoclosure () -> String = String(),
                   file: StaticString = #file,
                   line: UInt = #line)

Parameters

`condition`	The condition to test. `condition` is only evaluated in playgrounds and `-Onone` builds.
`message`	A string to print if `condition` is evaluated to `false`. The default is an empty string.
`file`	The file name to print with `message` if the assertion fails. The default is the file where `assert(_:_:file:line:)` is called.
`line`	The line number to print along with message if the assertion fails. The default is the line number where `assert(_:_:file:line:)` is called.


                    
                    
                    assertionFailure(error:file:line:)

Indicates that an internal sanity check failed.

Declaration

Swift

@inlinable
public func assertionFailure(error: Error,
                             file: StaticString = #file,
                             line: UInt = #line)

Parameters

`error`	The error that represents the assertion failure.
`file`	The file name to print with the description of `error`. The default is the file where `assertionFailure(error:file:line:)` is called.
`line`	The line number to print along with the description of `error`. The default is the line number where `assertionFailure(error:file:line:)` is called.


                    
                    
                    assertionFailure(_:file:line:)

Indicates that an internal sanity check failed.

Declaration

Swift

@inlinable
public func assertionFailure(_ message: @autoclosure () -> String = String(),
                             file: StaticString = #file,
                             line: UInt = #line)

Parameters

`message`	A string to print in a playground or `-Onone` build. The default is an empty string.
`file`	The file name to print with `message`. The default is the file where `assertionFailure(_:file:line:)` is called.
`line`	The line number to print along with `message`. The default is the line number where `assertionFailure(_:file:line:)` is called.


                    
                    
                    fatalError(_:file:line:)

Unconditionally reports a given error and stops execution.

Declaration

Swift

@inlinable
public func fatalError(_ error: Error,
                       file: StaticString = #file,
                       line: UInt = #line) -> Never

Parameters

`error`	The error to report.
`file`	The file name to print with the description of `error`. The default is the file where `fatalError(_:file:line:)` is called.
`line`	The line number to print with the description of `error`. The default is the line number where `fatalError(_:file:line:)` is called.


                    
                    
                    fatalError(_:file:line:)

Unconditionally prints a given message and stops execution.

Declaration

Swift

@inlinable
public func fatalError(_ message: @autoclosure () -> String = String(),
                       file: StaticString = #file,
                       line: UInt = #line) -> Never

Parameters

`message`	The string to print. The default is an empty string.
`file`	The file name to print with `message`. The default is the file where `fatalError(_:file:line:)` is called.
`line`	The line number to print along with `message`. The default is the line number where `fatalError(_:file:line:)` is called.


                    
                    
                    precondition(_:error:file:line:)

Checks a necessary condition for making forward progress.

Declaration

Swift

@inlinable
public func precondition(_ condition: @autoclosure () -> Bool,
                         error: Error,
                         file: StaticString = #file,
                         line: UInt = #line)

Parameters

`condition`	The condition to test. `condition is not evaluated in`-Ounchecked` builds.
`error`	The error that represents the precondition failure when `condition` evaluates to `false`.
`file`	The file name to print with the description of `error` if the precondition fails. The default is the file where `precondition(_:error:file:line:)` is called.
`line`	The line number to print along with the description of `error` if the precondition fails. The default is the line number where `precondition(_:error:file:line:)` is called.


                    
                    
                    precondition(_:_:file:line:)

Checks a necessary condition for making forward progress.

Declaration

Swift

@inlinable
public func precondition(_ condition: @autoclosure () -> Bool,
                         _ message: @autoclosure () -> String = String(),
                         file: StaticString = #file,
                         line: UInt = #line)

Parameters

`condition`	The condition to test. `condition` is not evaluated in `-Ounchecked` builds.
`message`	A string to print if `condition` is evaluated to `false` in a playground or `-Onone` build. The default is an empty string.
`file`	The file name to print with `message` if the precondition fails. The default is the file where `precondition(_:_:file:line:)` is called.
`line`	The line number to print along with `message` if the precondition fails. The default is the line number where `precondition(_:_:file:line:)` is called.


                    
                    
                    preconditionFailure(error:file:line:)

Indicates that a precondition was violated.

Declaration

Swift

@inlinable
public func preconditionFailure(error: Error,
                                file: StaticString = #file,
                                line: UInt = #line) -> Never

Parameters

`error`	The error that represents the precondition failure.
`file`	The file name to print with the description of `error`. The default is the file where `preconditionFailure(error:file:line:)` is called.
`line`	The line number to print along with the description of `error`. The default is the line number where `preconditionFailure(error:file:line:)` is called.


                    
                    
                    preconditionFailure(_:file:line:)

Indicates that a precondition was violated.

Declaration

Swift

@inlinable
public func preconditionFailure(_ message: @autoclosure () -> String = String(),
                                file: StaticString = #file,
                                line: UInt = #line) -> Never

Parameters

`message`	A string to print in a playground or `-Onone` build. The default is an empty string.
`file`	The file name to print with `message`. The default is the file where `preconditionFailure(_:file:line:)` is called.
`line`	The line number to print along with `message`. The default is the line number where `preconditionFailure(_:file:line:)` is called.