Package net.hydromatic.morel.type

Class TypeSystem

java.lang.Object

net.hydromatic.morel.type.TypeSystem

public class TypeSystem
extends java.lang.Object

A table that contains all types in use, indexed by their description (e.g. "int -> int").

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	TypeSystem.ForallHelper	Provides access to type variables from within a call to forallType(int, Function).
static class	TypeSystem.TemporaryType	Placeholder for a type that is being recursively defined.
private static class	TypeSystem.VariableCollector	Visitor that finds all TypeVar instances within a Type.

Field Summary

Fields

Modifier and Type	Field	Description
private java.util.Map<java.lang.String,Type>	typeByName
private java.util.Map<java.lang.String,Pair<DataType,Type>>	typeConstructorByName

Constructor Summary

Constructors

Constructor	Description
TypeSystem()

Method Summary

Modifier and Type	Method	Description
Type	apply(Type type, java.util.List<Type> types)
private boolean	areContiguousIntegers(java.lang.Iterable<java.lang.String> strings)	Returns whether the collection is ["1", "2", ...
DataType	dataType(java.lang.String name, java.util.List<TypeVar> typeVars, java.util.Map<java.lang.String,Type> tyCons)	Creates a data type.
Type	ensureClosed(Type type)	Converts a type into a ForallType if it has free type variables.
FnType	fnType(Type paramType, Type resultType)	Creates a function type.
Type	fnType(Type paramType, Type type1, Type type2, Type... moreTypes)	Creates a multi-step function type.
Type	forallType(int typeCount, java.util.function.Function<TypeSystem.ForallHelper,Type> builder)	Creates a "forall" type.
Type	forallType(java.lang.Iterable<TypeVar> typeVars, Type type)	Creates a "forall" type.
ListType	listType(Type elementType)	Creates a list type.
Type	lookup(java.lang.String name)	Looks up a type by name.
Type	lookupOpt(java.lang.String name)	Looks up a type by name, returning null if not found.
Pair<DataType,Type>	lookupTyCon(java.lang.String tyConName)
Type	recordType(java.util.SortedMap<java.lang.String,? extends Type> argNameTypes)	Creates a record type.
TypeSystem.TemporaryType	temporaryType(java.lang.String name)
Type	tupleType(java.util.List<? extends Type> argTypes)	Creates a tuple type.
Type	tupleType(Type... argTypes)	Creates a tuple type from an array of types.
TypeVar	typeVariable(int ordinal)
private static java.lang.StringBuilder	unparse(java.lang.StringBuilder builder, Type type, int left, int right)
private static java.lang.StringBuilder	unparseList(java.lang.StringBuilder builder, Op op, int left, int right, java.util.List<? extends Type> argTypes)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

typeByName

private final java.util.Map<java.lang.String,Type> typeByName

typeConstructorByName

private final java.util.Map<java.lang.String,Pair<DataType,Type>> typeConstructorByName

Constructor Detail

TypeSystem

public TypeSystem()

Method Detail

lookup

public Type lookup(java.lang.String name)

Looks up a type by name.

lookupOpt

public Type lookupOpt(java.lang.String name)

Looks up a type by name, returning null if not found.

fnType

public Type fnType(Type paramType,
                   Type type1,
                   Type type2,
                   Type... moreTypes)

Creates a multi-step function type.

For example, fnType(a, b, c, d) returns the same as fnType(a, fnType(b, fnType(c, d))), viz a → b → c → d.

fnType

public FnType fnType(Type paramType,
                     Type resultType)

Creates a function type.

tupleType

public Type tupleType(Type... argTypes)

Creates a tuple type from an array of types.

tupleType

public Type tupleType(java.util.List<? extends Type> argTypes)

Creates a tuple type.

listType

public ListType listType(Type elementType)

Creates a list type.

dataType

public DataType dataType(java.lang.String name,
                         java.util.List<TypeVar> typeVars,
                         java.util.Map<java.lang.String,Type> tyCons)

Creates a data type.

recordType

public Type recordType(java.util.SortedMap<java.lang.String,? extends Type> argNameTypes)

Creates a record type. (Or a tuple type if the fields are named "1", "2" etc.; or "unit" if the field list is empty.)

areContiguousIntegers

private boolean areContiguousIntegers(java.lang.Iterable<java.lang.String> strings)

Returns whether the collection is ["1", "2", ... n].

forallType

public Type forallType(int typeCount,
                       java.util.function.Function<TypeSystem.ForallHelper,Type> builder)

Creates a "forall" type.

forallType

public Type forallType(java.lang.Iterable<TypeVar> typeVars,
                       Type type)

Creates a "forall" type.

unparseList

private static java.lang.StringBuilder unparseList(java.lang.StringBuilder builder,
                                                   Op op,
                                                   int left,
                                                   int right,
                                                   java.util.List<? extends Type> argTypes)

unparse

private static java.lang.StringBuilder unparse(java.lang.StringBuilder builder,
                                               Type type,
                                               int left,
                                               int right)

temporaryType

public TypeSystem.TemporaryType temporaryType(java.lang.String name)

lookupTyCon

public Pair<DataType,Type> lookupTyCon(java.lang.String tyConName)

apply

public Type apply(Type type,
                  java.util.List<Type> types)

typeVariable

public TypeVar typeVariable(int ordinal)

ensureClosed

public Type ensureClosed(Type type)

Converts a type into a ForallType if it has free type variables.