ucDefine

See Also: ucDefineVariable, ucDefineFunction, ucDefineOperator, and ucDefineSyntax.

Defines an item.

ucDefine(Definition [, Misc1, [, Misc2 [, Misc3 [, tHandle]]]])

Parameters

Definition

Required.� Definition is a string argument that starts with a keyword corresponding with the kind of item you want to define, followed by one or two colons, and the definition itself.� Some of the possible definition "keywords" include:� Var, Func, Op, and Syntax, corresponding respectively with definitions for variables, functions, operators, and syntax constructs.� These overlap with the functionality of ucDefineVariable, ucDefineFunction, ucDefineOperator, and ucDefineSyntax.� Additional keywords include: Const (for constants), DataType, Macro, and Token.

Misc1, Misc2, Misc3

Optional.� These are numeric arguments that may correspond with properties or memory addresses, depending on how the particular definition is set up.

tHandle

Optional.� See Thread Handling.

Remarks

• Some of the functionality associated with ucDefine is beyond the scope of uCalc Fast Math Parser.� Visit www.ucalc.com for further documentation.
• Func or Op followed by one colon denotes either an end-user function or operator definition, or callback definition that is non-Native.� Two colons are used for Native callbacks, which are faster than non-Native callbacks.

ucDefineFunction "Native: f(x)", AddressOf MyFunction

is the equivalent of:

ucDefine "Func:: f(x)", AddressOf MyFunction

Note to C++ users

In the uCalc header file for Visual C++ and Borland C++ Builder, ucDefine is overloaded with two slightly different routines.� If ucDefine will have more than two arguments, and the second argument is 0, then you should pass either (DWORD)0 or empty quotes "" for that argument, especially in VC++, otherwise ambiguity between the two definitions will cause it not to compile.�� So for instance in VC++, assuming tHandle is defined already, you should use the second or third line below instead of the first (and in C#, you can only use the third line):

ucDefine("Syntax: a ::= b", 0, 0, 0, tHandle); // This line will not compile in C++

ucDefine("Syntax: a ::= b", (DWORD)0, 0, 0, tHandle); // This line will compile in C++

ucDefine("Syntax: a ::= b", "", 0, 0, tHandle); // This line will compile in C++

Example:

In this example, the first line defines a variable named x, which stores an initial numeric value of 123.� The second line defines a constant named Pi, which stores the computed value of 3.14159... .� The third line defines an end-user function.� The fourth line defines an infix operator named ShiftLeft.� The line after that defines a VB-like syntax construct that accepts binary numbers such as &b1011001.� The last line defines a macro.

Visual Basic

ucDefine "Var: x = 123"

ucDefine "Const: Pi = Atan(1) * 4"

ucDefine "Func: f(x) = x^2"

ucDefine "Op: 20 {x} ShiftLeft {y} := x * 2^y"

ucDefine "Syntax: {'&b'}{Number:'[0-1]+'} ::= BaseConvert('{Number}', 2)"

ucDefine "Macro: Plus(x) = x + x"

New or enhanced in version 3.0

� Keywords: RightToLeft and Overwrite.

Note: ucDefine() is no longer available to the end user in version 3.0 (it is still available at the source code level though).

New or enhanced in version 2.96

• The end-user can now use ucDefine as well within an expression.

New or enhanced in version 2.9+

• This feature was added in version 2.9.� It allows you to pass functionality on to end-users that would have previously been mostly restricted to the application developer.