water.rapids.ast.prims.search

Class AstWhichFunc

java.lang.Object

water.Iced<T>

water.rapids.ast.AstRoot<T>

water.rapids.ast.AstPrimitive<T>

water.rapids.ast.AstBuiltin<AstWhichFunc>

water.rapids.ast.prims.search.AstWhichFunc

All Implemented Interfaces:

java.io.Externalizable, java.io.Serializable, java.lang.Cloneable, Freezable<AstWhichFunc>

Direct Known Subclasses:

AstWhichMax, AstWhichMin

public abstract class AstWhichFunc
extends AstBuiltin<AstWhichFunc>

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
AstWhichFunc()

Method Summary

Modifier and Type	Method and Description
Val	apply(Env env, Env.StackHelp stk, AstRoot[] asts) Primary method to invoke this function, passing all the parameters as the `asts` list.
java.lang.String[]	args() List of argument names.
abstract double	init()
int	nargs() Number of function's arguments + 1.
abstract double	op(Vec l)
abstract java.lang.String	searchVal()
java.lang.String	str() String representation of this Ast object in the Rapids language.

Methods inherited from class water.rapids.ast.AstBuiltin

exec

Methods inherited from class water.rapids.ast.AstPrimitive

description, example, exec

Methods inherited from class water.rapids.ast.AstRoot

toString

Methods inherited from class water.Iced

asBytes, clone, copyOver, frozenType, read, readExternal, readJSON, reloadFromBytes, toJsonBytes, toJsonString, write, writeExternal, writeJSON

Methods inherited from class java.lang.Object

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

Constructor Detail

AstWhichFunc

public AstWhichFunc()

Method Detail

args

public java.lang.String[] args()

Description copied from class: AstPrimitive

List of argument names. The length of the returned array should be equal to `nargs() - 1` (unless `nargs()` returns -1, in which case this function may return {"..."} or something similar).

Specified by:

args in class AstPrimitive<AstWhichFunc>

nargs

public int nargs()

Description copied from class: AstPrimitive

Number of function's arguments + 1. Thus, a binary operator like '+' should be declared with 3 nargs: ["+", lhs, rhs]. For variable-argument functions this method should return -1.

Specified by:

nargs in class AstPrimitive<AstWhichFunc>

str

public java.lang.String str()

Description copied from class: AstRoot

String representation of this Ast object in the Rapids language. For AstPrimitives this is the name of the function; for AstParameters this is either the name of the variable, or the value of the numeric constant that the parameter represents. For more complicated constructs such as AstExec or AstFunction this method should return those objects as a Rapids string.

Specified by:

str in class AstRoot<AstWhichFunc>

op

public abstract double op(Vec l)

searchVal

public abstract java.lang.String searchVal()

init

public abstract double init()

apply

public Val apply(Env env,
                 Env.StackHelp stk,
                 AstRoot[] asts)

Description copied from class: AstBuiltin

Primary method to invoke this function, passing all the parameters as the `asts` list.

The default implementation of this method executes all Asts within the provided environment, and then calls AstBuiltin.exec(Val[]) passing it the arguments as the list of Vals. A derived class will then only need to override the second `exec()` function which is much simpler.

However for certain functions (such as short-circuit boolean operators) executing all arguments is not desirable -- these functions would have to override this more general method.

Overrides:

apply in class AstBuiltin<AstWhichFunc>

Parameters:

env - Current execution environment. Variables are looked up here.

stk - TODO need clarification

asts - List of AstRoot expressions that are arguments to the function. First element in this list is the function itself.

Returns:

value resulting from calling the function with the provided list of arguments.