Safe Haskell | None |
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Computations involving the generation of fresh symbols.

The notion of what is a symbol is abstracted by the `Gensym`

class.
Then, we provide the `SymbolGen`

monad and `SymbolGenT`

monad transformer,
in which symbols may be generated.

Symbols are generated deterministically, but also without reference to any other sources of symbols, such as the programmer's algorithms, user input or other SymbolGen monads. Therefore, make sure the symbols you generate are trivially distinct from all other sources of symbols.

- class Gensym s where
- gensym :: (Gensym s, Monad m) => SymbolGenT s m s
- type SymbolGen s = SymbolGenT s Identity
- runSymbolGen :: Gensym s => SymbolGen s a -> a
- data SymbolGenT s m a
- runSymbolGenT :: (Gensym s, Monad m) => SymbolGenT s m a -> m a

# Generate Symbols

Class for types that can provide an infinite supply of distinct values.

The initial symbol generated.

Given the last symbol generated, generate the next. Must be distinct from all other symbols generated.

gensym :: (Gensym s, Monad m) => SymbolGenT s m sSource

Generate a fresh symbol. Of course, this monad does not know
what other sources of symbols there are, so make sure your `Gensym`

instance generates symbols distinct from all others.

# Symbol Generator Monad

type SymbolGen s = SymbolGenT s IdentitySource

Synonym for SymbolGenT over Identity.

runSymbolGen :: Gensym s => SymbolGen s a -> aSource

Synonym for

.
`runIdentity`

. `runSymbolGenT`

# Symbol Generator Monad Transformer

data SymbolGenT s m a Source

Monad transformer adding the capability of generating fresh symbols.

MonadTrans (SymbolGenT s) | |

Monad m => Monad (SymbolGenT s m) | |

Monad m => Functor (SymbolGenT s m) | |

Monad m => Applicative (SymbolGenT s m) | |

C m => C (SymbolGenT s m) | |

MonadIO m => MonadIO (SymbolGenT s m) |

runSymbolGenT :: (Gensym s, Monad m) => SymbolGenT s m a -> m aSource

Perform a computation involving generating fresh symbols.