resolution

README

resolution

A Go implementation of SLD and SLG resolution

Documentation

Overview

This package implements the SLG resolution.

Index

• type AST
• type ASTRule
  • func (a *ASTRule) Description() string
  • func (a *ASTRule) Sem() *Rule
• type ASTTerm
• type ASTValue
  • func (a *ASTValue) Description() string
  • func (a *ASTValue) Sem(vars map[string]*Variable) Term
• type ASTVar
  • func (a *ASTVar) Description() string
  • func (a *ASTVar) Sem(vars map[string]*Variable) Term
• type Context
  • func NewContext() *Context
  • func (c *Context) Clone() *Context
• type Rule
  • func NewRule(head *Value, body []*Value) *Rule
  • func (r *Rule) AddUse()
  • func (r *Rule) InstantiateVariables() (*Value, []*Value)
  • func (r *Rule) RelinquishUse()
  • func (r *Rule) String() string
• type Server
  • func NewServer() *Server
• type Signature
• type Snapshot
• type Term
• type Theory
  • func NewTheory(rules []*Rule) *Theory
  • func NewTheoryFromSource(code string) (*Theory, error)
  • func (th *Theory) AddRule(rule *Rule)
  • func (th *Theory) AddRules(rules []*Rule)
  • func (th *Theory) AddRulesFromSource(code string) error
  • func (th *Theory) Infer(context *Context, goal *Value, cb func(*Context) bool)
  • func (th *Theory) InferTabled(context *Context, goal *Value, cb func(*Context) bool)
  • func (th *Theory) Rollback(ss *Snapshot)
  • func (th *Theory) Snapshot() *Snapshot
  • func (th *Theory) String() string
• type Value
  • func NewValue(vars map[string]*Variable, functor string, args ...string) *Value
  • func (p *Value) CtxString(context *Context) string
  • func (v *Value) Ground(context *Context) *Value
  • func (p *Value) InstantiateVariables(vars map[string]*Variable) *Value
  • func (v *Value) Signature() Signature
  • func (v *Value) TableSignature(context *Context) string
  • func (p1 *Value) Unify(context *Context, p2 Term, cb func(*Context))
• type Variable
  • func (v *Variable) Bind(context *Context, t Term)
  • func (v *Variable) CtxString(context *Context) string
  • func (v *Variable) Ground(context *Context) *Value
  • func (v *Variable) Pointee(context *Context) Term
  • func (v *Variable) SetPointee(context *Context, t Term)
  • func (v *Variable) Unify(context *Context, t Term, cb func(*Context))

Types

type AST

type AST interface {
	Description() string
}

An abstract AST.

type ASTRule

type ASTRule struct {
	// contains filtered or unexported fields
}

A syntactic rule.

func (*ASTRule) Description

func (a *ASTRule) Description() string

A textual representation of the rule.

func (*ASTRule) Sem

func (a *ASTRule) Sem() *Rule

type ASTTerm

type ASTTerm interface {
	AST
	Sem(vars map[string]*Variable) Term
}

type ASTValue

type ASTValue struct {
	// contains filtered or unexported fields
}

func (*ASTValue) Description

func (a *ASTValue) Description() string

func (*ASTValue) Sem

func (a *ASTValue) Sem(vars map[string]*Variable) Term

type ASTVar

type ASTVar struct {
	// contains filtered or unexported fields
}

func (*ASTVar) Description

func (a *ASTVar) Description() string

func (*ASTVar) Sem

func (a *ASTVar) Sem(vars map[string]*Variable) Term

type Context

type Context struct {
	// contains filtered or unexported fields
}

func NewContext

func NewContext() *Context

func (*Context) Clone

func (c *Context) Clone() *Context

type Rule

type Rule struct {
	Head *Value
	Body []*Value
	// contains filtered or unexported fields
}

func NewRule

func NewRule(head *Value, body []*Value) *Rule

func (*Rule) AddUse

func (r *Rule) AddUse()

func (*Rule) InstantiateVariables

func (r *Rule) InstantiateVariables() (*Value, []*Value)

func (*Rule) RelinquishUse

func (r *Rule) RelinquishUse()

func (*Rule) String

func (r *Rule) String() string

type Server

type Server struct {
	// contains filtered or unexported fields
}

func NewServer

func NewServer() *Server

type Signature

type Signature struct {
	Functor string
	Arity   int
}

type Snapshot

type Snapshot struct {
	// contains filtered or unexported fields
}

type Term

type Term interface {
	CtxString(*Context) string
	Unify(*Context, Term, func(*Context))
	Ground(*Context) *Value
}

type Theory

type Theory struct {
	//Rules []*Rule
	Rules map[Signature][]*Rule
}

func NewTheory

func NewTheory(rules []*Rule) *Theory

func NewTheoryFromSource

func NewTheoryFromSource(code string) (*Theory, error)

Creates a new theory from the provided source code.

func (*Theory) AddRule

func (th *Theory) AddRule(rule *Rule)

func (*Theory) AddRules

func (th *Theory) AddRules(rules []*Rule)

func (*Theory) AddRulesFromSource

func (th *Theory) AddRulesFromSource(code string) error

Adds rules from the provided source code.

func (*Theory) Infer

func (th *Theory) Infer(context *Context, goal *Value, cb func(*Context) bool)

func (*Theory) InferTabled

func (th *Theory) InferTabled(context *Context, goal *Value, cb func(*Context) bool)

func (*Theory) Rollback

func (th *Theory) Rollback(ss *Snapshot)

func (*Theory) Snapshot

func (th *Theory) Snapshot() *Snapshot

func (*Theory) String

func (th *Theory) String() string

type Value

type Value struct {
	Functor string
	Args    []Term
}

func NewValue

func NewValue(vars map[string]*Variable, functor string, args ...string) *Value

func (*Value) CtxString

func (p *Value) CtxString(context *Context) string

func (*Value) Ground

func (v *Value) Ground(context *Context) *Value

func (*Value) InstantiateVariables

func (p *Value) InstantiateVariables(vars map[string]*Variable) *Value

func (*Value) Signature

func (v *Value) Signature() Signature

func (*Value) TableSignature

func (v *Value) TableSignature(context *Context) string

func (*Value) Unify

func (p1 *Value) Unify(context *Context, p2 Term, cb func(*Context))

Unifies two terms using the provided context.

type Variable

type Variable struct {
	// contains filtered or unexported fields
}

func (*Variable) Bind

func (v *Variable) Bind(context *Context, t Term)

func (*Variable) CtxString

func (v *Variable) CtxString(context *Context) string

func (*Variable) Ground

func (v *Variable) Ground(context *Context) *Value

func (*Variable) Pointee

func (v *Variable) Pointee(context *Context) Term

func (*Variable) SetPointee

func (v *Variable) SetPointee(context *Context, t Term)

func (*Variable) Unify

func (v *Variable) Unify(context *Context, t Term, cb func(*Context))