Lambda

This code has been declared by its author to be Public Domain code.

Lambda by Azathoth

2007

This is like the Lambda found in Lisp, Python, Lua, etc.
Wrote it in afew hours and its likely not very speed or memory efficient, and probably has bugs. Not much comments either.
Currently only has Multiply and Addition Types but its easy to add more.

*LType is a wrapper like Type that can store Lambda and Strings/Numbers, though when the value of a Lambda function is retreived it gets invoked.
LType.Str and Num are stored and handled the same and could probably remove Num.
LType.Set will try to guess the passed object if t=none (default)

Strict

Type Lambda

	Field args:TList=CreateList()

	Method PushArg(a:LType)
		args.AddLast(a)
	EndMethod
	
	Method GetArg:LType(i)
		Return LType(args.ValueAtIndex(i))
	EndMethod

	Method Invoke:LType()
	EndMethod
EndType

Type LAdd Extends Lambda

	Function Add:LAdd(x:LType,y:LType)
		Local n:LAdd=New LAdd
		
		n.PushArg(x); n.PushArg(y)
		Return n
	EndFunction
	
	Method Invoke:LType()
		Local r:LType=LType.Create(String(GetArg(0).ToDouble()+GetArg(1).ToDouble()),LType.Num)
		
		Return r
	EndMethod
EndType

Type LMul Extends Lambda

	Function Mul:LMul(x:LType,y:LType)
		Local n:LMul=New LMul
		
		n.PushArg(x); n.PushArg(y)
		Return n
	EndFunction
	
	Method Invoke:LType()
		Local r:LType=LType.Create(String(GetArg(0).ToDouble()*GetArg(1).ToDouble()),LType.Num)
		
		Return r
	EndMethod
EndType

Type LType
	Const None=0
	Const Lambda=1
	Const Num=2
	Const Str=3

	Field _data:Object
	Field _type:Int
	
	Function Create:LType(value:Object=Null,t=None)
		Local n:LType=New LType
		n.Set(value,t)
		Return n
	EndFunction
	
	Method Set(value:Object=Null,t=None)
		If t=None And value<>Null		' Guess type
			If .Lambda(value)
				_type=LType.Lambda
			ElseIf String(value)
				_type=Str
			EndIf
		Else
			_type=t
		EndIf
		_data=value
	EndMethod
	
	Method ToString:String()
		If _type=Num Or _type=Str
			Return String(_data)
		ElseIf _type=LType.Lambda
			Return .Lambda(_data).Invoke().ToString()
		EndIf
	EndMethod
	
	Method ToDouble:Double()
		Return ToString().ToDouble()
	EndMethod
	
EndType


' *** Test

Local test:Lambda=LMul.Mul(.. 
	LType.Create("10"),LType.Create(LAdd.Add( LType.Create("1"),LType.Create("1") ))..
	)

Print "10*(1+1)"								
Print test.Invoke().ToString()
Print "--~n"

' *** Test with 'variables'


Local UserArg1:LType=New LType

test=LMul.Mul(.. 
	UserArg1,LType.Create(LAdd.Add( LType.Create("1"),LType.Create("1") ))..
	)
								

UserArg1.Set("100")
Print "UserArg1=100"
Print "UserArg1*(1+1)"
Print test.Invoke().ToString()

Comments

Warpy

2008

Very interesting!

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