Package net.hydromatic.morel.ast

Class Core.FromStep

java.lang.Object

net.hydromatic.morel.ast.AstNode

net.hydromatic.morel.ast.Core.BaseNode

net.hydromatic.morel.ast.Core.FromStep

Direct Known Subclasses:

Core.Group, Core.Order, Core.Scan, Core.SetStep, Core.Skip, Core.Take, Core.Unorder, Core.Where, Core.Yield

Enclosing class:

Core

public abstract static class Core.FromStep
extends Core.BaseNode

A step in a from expression - where, group or order.

Field Summary

Fields

Modifier and Type	Field	Description
final Core.StepEnv	env

Fields inherited from class net.hydromatic.morel.ast.AstNode

op, pos

Constructor Summary

Constructors

Constructor	Description
FromStep(Op op, Core.StepEnv env)

Method Summary

Modifier and Type	Method	Description
abstract Core.FromStep	accept(Shuttle shuttle)	Accepts a shuttle, calling the Shuttle.visit(net.hydromatic.morel.ast.Ast.Literal) method appropriate to the type of this node, and returning the result.
boolean	isOrdered(boolean inputIsOrdered)	Returns whether the output of this step is ordered, given whether the input is ordered.
(package private) final AstWriter	unparse(AstWriter w, int left, int right)
protected abstract AstWriter	unparse(AstWriter w, Core.From from, int ordinal, int left, int right)

Methods inherited from class net.hydromatic.morel.ast.Core.BaseNode

accept

Methods inherited from class net.hydromatic.morel.ast.AstNode

toString, unparse

Methods inherited from class java.lang.Object

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

Field Details

env

public final Core.StepEnv env

Constructor Details

FromStep

FromStep(Op op,
 Core.StepEnv env)

Method Details

isOrdered

public boolean isOrdered(boolean inputIsOrdered)

Returns whether the output of this step is ordered, given whether the input is ordered.

For example, Core.Where and Core.Yield are ordered if and only if their input is ordered; Core.Order is always ordered; Core.Group is unordered.

unparse

final AstWriter unparse(AstWriter w,
 int left,
 int right)

Specified by:

unparse in class AstNode

unparse

protected abstract AstWriter unparse(AstWriter w,
 Core.From from,
 int ordinal,
 int left,
 int right)

accept

public abstract Core.FromStep accept(Shuttle shuttle)

Description copied from class: AstNode

Accepts a shuttle, calling the Shuttle.visit(net.hydromatic.morel.ast.Ast.Literal) method appropriate to the type of this node, and returning the result.

Overrides:

accept in class Core.BaseNode