Symbol package:ghc-internal

(Kind) This is the kind of type-level symbols.

Haskell symbol, e.g. >>, :%

Concatenation of type-level symbols.

Comparison of type-level symbols, as a function.

Extending a type-level symbol with a type-level character

This class gives the string associated with a type-level symbol. There are instances of the class for every concrete literal: "hello", etc.

A value-level witness for a type-level symbol. This is commonly referred to as a singleton type, as for each s, there is a single value that inhabits the type SSymbol s (aside from bottom). The definition of SSymbol is intentionally left abstract. To obtain an SSymbol value, use one of the following:

1. The symbolSing method of KnownSymbol.
2. The SSymbol pattern synonym.
3. The withSomeSSymbol function, which creates an SSymbol from a String.

A explicitly bidirectional pattern synonym relating an SSymbol to a KnownSymbol constraint. As an expression: Constructs an explicit SSymbol s value from an implicit KnownSymbol s constraint:

SSymbol @s :: KnownSymbol s => SSymbol s

As a pattern: Matches on an explicit SSymbol s value bringing an implicit KnownSymbol s constraint into scope:

f :: SSymbol s -> ..
f SSymbol = {- KnownSymbol s in scope -}

This type represents unknown type-level symbols.

This type family yields type-level Just storing the first character of a symbol and its tail if it is defined and Nothing otherwise.

A pattern that can be used to manipulate the String that an SSymbol s contains under the hood. When using this pattern to construct an SSymbol s, the actual String being stored in the SSymbol must be equal to (the contents of) s. The compiler will not help you verify this, hence the 'unsafe' name.

Like sameSymbol, but if the symbols aren't equal, this additionally provides proof of LT or GT.

We either get evidence that this function was instantiated with the same type-level symbols, or that the type-level symbols are distinct.

Return the String corresponding to s in an SSymbol s value.

We either get evidence that this function was instantiated with the same type-level symbols, or Nothing.

Convert a string into an unknown type-level symbol.

Convert an explicit SSymbol s value into an implicit KnownSymbol s constraint.

Convert a String into an SSymbol s value, where s is a fresh type-level symbol.