Class GrammarSymbolExtensions

Namespace

Farkle.Builder

Assembly

Farkle.dll

Contains extension methods that to set configuration options on IGrammarSymbol and IGrammarSymbol<T>.

public static class GrammarSymbolExtensions

Inheritance

object

GrammarSymbolExtensions

Remarks

These methods apply to specific symbols within the grammar and do not modify the object they are called on. Instead, they return a new object with the requested configuration option changed.

Changing configuration on a symbol does not change the symbol's identity and the changed symbol instance will be treated as the same symbol as before when building the grammar. Consult the documentation of each method for information on what happens when a symbol exists in a grammar with varying configuration options.

Methods

AddSpecialName(IGrammarSymbol, string)

Adds a special name to the symbol, which is used to uniquely identify it within the grammar.

public static IGrammarSymbol AddSpecialName(this IGrammarSymbol symbol, string name)

Parameters

symbol IGrammarSymbol

name string

Returns

IGrammarSymbol

Remarks

If a grammar has multiple symbols with the same special name, building will fail.

Calling this method multiple times will add multiple special names to the symbol.

See Also

GetSymbolFromSpecialName(string, bool)

AddSpecialName<T>(IGrammarSymbol<T>, string)

Adds a special name to the symbol, which is used to uniquely identify it within the grammar.

public static IGrammarSymbol<T> AddSpecialName<T>(this IGrammarSymbol<T> symbol, string name)

Parameters

symbol IGrammarSymbol<T>

name string

Returns

IGrammarSymbol<T>

Type Parameters

T

Remarks

If a grammar has multiple symbols with the same special name, building will fail.

Calling this method multiple times will add multiple special names to the symbol.

See Also

GetSymbolFromSpecialName(string, bool)

Cast(IGrammarSymbol)

Changes the type of IGrammarSymbol to a generic IGrammarSymbol<T> of type object, forcing it to return a value.

public static IGrammarSymbol<object?> Cast(this IGrammarSymbol symbol)

Parameters

symbol IGrammarSymbol

The grammar symbol.

Returns

IGrammarSymbol<object>

An IGrammarSymbol<T> that returns the object symbol would return. If symbol had been created with the untyped API, the returned object will be null.

Many<T, TCollection>(IGrammarSymbol<T>, bool)

Creates a symbol that can match the given symbol multiple times.

public static IGrammarSymbol<TCollection> Many<T, TCollection>(this IGrammarSymbol<T> symbol, bool atLeastOnce = false) where TCollection : ICollection<T>, new()

Parameters

symbol IGrammarSymbol<T>

The symbol to match multiple times.

atLeastOnce bool

Whether symbol must be matched at least once. Optional, defaults to false

Returns

IGrammarSymbol<TCollection>

Type Parameters

T

The type of values the symbol returns.

TCollection

The type of collection to place the values of the symbol in. Must implement ICollection<T>.

Nullable<T>(IGrammarSymbol<T>)

Creates a symbol that can match either the given symbol once, or nothing. In the latter case it returns default.

public static IGrammarSymbol<T?> Nullable<T>(this IGrammarSymbol<T> symbol) where T : struct

Parameters

symbol IGrammarSymbol<T>

The symbol to make nullable.

Returns

IGrammarSymbol<T?>

Type Parameters

T

The type of values the symbol returns.

See Also

Optional<T>(IGrammarSymbol<T>)

Optional<T>(IGrammarSymbol<T>)

Creates a symbol that can match either the given symbol once, or nothing. In the latter case it returns null.

public static IGrammarSymbol<T?> Optional<T>(this IGrammarSymbol<T> symbol)

Parameters

symbol IGrammarSymbol<T>

Returns

IGrammarSymbol<T>

Type Parameters

T

See Also

Nullable<T>(IGrammarSymbol<T>)

Select<T, TNew>(IGrammarSymbol<T>, Func<T, TNew>, string?)

Creates a symbol that matches the given symbol and then applies a transformation to its returning value.

public static IGrammarSymbol<TNew> Select<T, TNew>(this IGrammarSymbol<T> symbol, Func<T, TNew> selector, string? name = null)

Parameters

symbol IGrammarSymbol<T>

The symbol to transform.

selector Func<T, TNew>

The transformation to apply to the value of symbol.

name string

The name of the new symbol. If not provided, a default name will be generated.

Returns

IGrammarSymbol<TNew>

Type Parameters

T

The type of values the symbol returns.

TNew

The type of values the new symbol will return.

SeparatedBy<T, TCollection>(IGrammarSymbol<T>, IGrammarSymbol, bool)

Creates a symbol that can match the given symbol multiple times, separated by another symbol.

public static IGrammarSymbol<TCollection> SeparatedBy<T, TCollection>(this IGrammarSymbol<T> symbol, IGrammarSymbol separator, bool atLeastOnce = false) where TCollection : ICollection<T>, new()

Parameters

symbol IGrammarSymbol<T>

The symbol to match multiple times.

separator IGrammarSymbol

The symbol to match between the instances of symbol.

atLeastOnce bool

Whether symbol must be matched at least once. Optional, defaults to false

Returns

IGrammarSymbol<TCollection>

Type Parameters

T

The type of values the symbol returns.

TCollection

The type of collection to place the values of the symbol in. Must implement ICollection<T>.