Class Result<TToken, T>
Represents the result of parsing. A parse result may be successful (Success == true), in which case it contains a value, or it may be a failure, in which case it contains an error.
Inheritance
- Object
- Result<TToken, T>
Declaration
public class Result<TToken, T> : ObjectType Parameters
| Name | Description |
|---|---|
TToken |
The type of the tokens in the parser's input stream. |
T |
The type of the value returned by the parser. |
Properties
Error
The parse error.
Declaration
public ParseError<TToken> Error { get; }Property Value
| Type | Description |
|---|---|
ParseError<TToken> |
Exceptions
| Type | Condition |
|---|---|
Thrown when the result was a successful one. |
Success
Did the parse succeed?.
Declaration
public bool Success { get; }Property Value
| Type | Description |
|---|---|
A value indicating whether the parse was successful. |
Value
The parser's return value.
Declaration
public T Value { get; }Property Value
| Type | Description |
|---|---|
T |
Exceptions
| Type | Condition |
|---|---|
Thrown when the result was not a successful one. |
Methods
Cast<U>()
Cast the value contained in the result to the specified output type.
Declaration
public Result<TToken, U> Cast<U>()Returns
| Type | Description |
|---|---|
Result<TToken, U> |
A result containing this result's value casted to |
Type Parameters
| Name | Description |
|---|---|
U |
The type to cast the contained value to. |
Exceptions
| Type | Condition |
|---|---|
Thrown when the contained value is not an instance of |
GetValueOrDefault()
Get the value, or return a default value.
Declaration
public T GetValueOrDefault()Returns
| Type | Description |
|---|---|
T |
The value if Success is true, or a default value. |
GetValueOrDefault(T)
Get the value, or return the specified default value.
Declaration
public T GetValueOrDefault(T default)Parameters
| Type | Name | Description |
|---|---|---|
T |
default |
The default value. |
Returns
| Type | Description |
|---|---|
T |
The value if Success is true, or the specified default value. |
GetValueOrDefault(Func<T>)
Get the value, or return the result of calling the specified function.
Declaration
public T GetValueOrDefault(Func<T> value)Parameters
| Type | Name | Description |
|---|---|---|
Func<T> |
value |
A function which computes a default value. |
Returns
| Type | Description |
|---|---|
T |
The value if Success is true, or the result of calling the specified function. |
Match<U>(Func<T, U>, Func<ParseError<TToken>, U>)
Tear down this parse result using a function for the two possible outcomes.
If Success == true, success will be called. Otherwise, failure will be called.
Declaration
public U Match<U>(Func<T, U> success, Func<ParseError<TToken>, U> failure)Parameters
| Type | Name | Description |
|---|---|---|
Func<T, U> |
success |
Called when the result has a value. |
Func<ParseError<TToken>, U> |
failure |
Called when the result does not have a value. |
Returns
| Type | Description |
|---|---|
U |
The result of calling the |
Type Parameters
| Name | Description |
|---|---|
U |
The return type. |
Or(Result<TToken, T>)
Choose the first successful result.
Declaration
public Result<TToken, T> Or(Result<TToken, T> result)Parameters
| Type | Name | Description |
|---|---|---|
Result<TToken, T> |
result |
A fallback result if this one has an error. |
Returns
| Type | Description |
|---|---|
Result<TToken, T> |
This result, if Success == true, or |
Or(Func<Result<TToken, T>>)
Choose the first successful result.
Declaration
public Result<TToken, T> Or(Func<Result<TToken, T>> result)Parameters
| Type | Name | Description |
|---|---|---|
result |
A fallback result if this one has an error. |
Returns
| Type | Description |
|---|---|
Result<TToken, T> |
This result, if Success == true, or the result of calling |
Select<U>(Func<T, U>)
Project the value contained in the result.
Declaration
public Result<TToken, U> Select<U>(Func<T, U> selector)Parameters
| Type | Name | Description |
|---|---|---|
Func<T, U> |
selector |
A transformation function to apply to the contained value. |
Returns
| Type | Description |
|---|---|
Result<TToken, U> |
The result of applying the transformation function to the contained value. |
Type Parameters
| Name | Description |
|---|---|
U |
The type of the resulting value. |
SelectMany<U>(Func<T, Result<TToken, U>>)
Projects the value of the result into a result, and flattens the resulting value into a single result.
Declaration
public Result<TToken, U> SelectMany<U>(Func<T, Result<TToken, U>> selector)Parameters
| Type | Name | Description |
|---|---|---|
selector |
A transformation function to apply to the contained value. |
Returns
| Type | Description |
|---|---|
Result<TToken, U> |
The final result. |
Type Parameters
| Name | Description |
|---|---|
U |
The type of the resulting possibly-absent value. |
SelectMany<U, R>(Func<T, Result<TToken, U>>, Func<T, U, R>)
Projects the value of the result into a result, and flattens the resulting value into a single result, applying a result selector function to the two values.
Declaration
public Result<TToken, R> SelectMany<U, R>(Func<T, Result<TToken, U>> selector, Func<T, U, R> result)Parameters
| Type | Name | Description |
|---|---|---|
selector |
A transformation function to apply to the contained value. |
|
Func<T, U, R> |
result |
A transformation function to apply to the contained value and the value contained in the selected Maybe<T>. |
Returns
| Type | Description |
|---|---|
Result<TToken, R> |
The result of applying |
Type Parameters
| Name | Description |
|---|---|
U |
The type of the value to select. |
R |
The type of the resulting possibly-absent value. |