io.permazen.parse.func

Class SimpleFunction

java.lang.Object

io.permazen.parse.func.AbstractFunction

io.permazen.parse.func.SimpleFunction

All Implemented Interfaces:

Function

Direct Known Subclasses:

ConcatFunction, CountFunction, LimitFunction, ListFunction, SimpleCliFunction, UpgradeFunction, VersionFunction

public abstract class SimpleFunction
extends AbstractFunction

Simplified Function implementation for when the parameters are all normal expressions.

Field Summary

Fields

Modifier and Type	Field and Description
protected int	maxArgs
protected int	minArgs

Fields inherited from class io.permazen.parse.func.AbstractFunction

log, name, spaceParser

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	SimpleFunction(String name, int minArgs, int maxArgs) Constructor.

Method Summary

Modifier and Type	Method and Description
Value	apply(ParseSession session, Object info) Evaluate this function.
protected abstract Value	apply(ParseSession session, Value[] params) Apply this function to the given values.
int	getMaxArgs() Get the maximum number of arguments allowed (inclusive).
int	getMinArgs() Get the minimum number of arguments allowed (inclusive).
Node[]	parseParams(ParseSession session, ParseContext ctx, boolean complete) Parse function parameters.

Methods inherited from class io.permazen.parse.func.AbstractFunction

getHelpDetail, getName, getSessionModes, parseExpressionParams, parseNextParameter

Methods inherited from class java.lang.Object

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

Methods inherited from interface io.permazen.parse.func.Function

getHelpSummary, getUsage

Field Detail

minArgs

protected final int minArgs

maxArgs

protected final int maxArgs

Constructor Detail

SimpleFunction

protected SimpleFunction(String name,
                         int minArgs,
                         int maxArgs)

Constructor.

Parameters:

name - function name

minArgs - minimum number of arguments (inclusive)

maxArgs - maximum number of arguments (inclusive)

Method Detail

getMinArgs

public int getMinArgs()

Get the minimum number of arguments allowed (inclusive).

Returns:

minimum required function arguments

getMaxArgs

public int getMaxArgs()

Get the maximum number of arguments allowed (inclusive).

Returns:

maximum allowed function arguments

parseParams

public final Node[] parseParams(ParseSession session,
                                ParseContext ctx,
                                boolean complete)

Description copied from interface: Function

Parse function parameters.

The ctx will be pointing at the first parameter (if any) or closing parenthesis. This method should parse (but not evaluate) function parameters up through the closing parenthesis. The return value is an opaque value representing the parsed parameters and subsequently passed to apply().

Parameters:

session - parse session

ctx - parse context

complete - false if parse is "for real", true if only for tab completion calculation

Returns:

parsed parameters object to be passed to apply()

apply

public final Value apply(ParseSession session,
                         Object info)

Description copied from interface: Function

Evaluate this function. There will be a transaction open.

Parameters:

session - parse session

info - parsed parameters returned by parseParams()

Returns:

value returned by this function

apply

protected abstract Value apply(ParseSession session,
                               Value[] params)

Apply this function to the given values.

Parameters:

session - parse session

params - parsed parameters; will already be checked between getMinArgs() and getMaxArgs()

Returns:

value returned by this function

Throws:

RuntimeException - if there is an error