|Column Tag:||Tools of the Trade
By Dave Kelly, MacTutor Editorial Board
Most of you have seen Heizer Softwares CompileIt! 2.0 advertised. Lets take a look at CompileIt! and what it can do for you. HyperCard is an easy going environment to work with. Because of that, HyperTalk has not been a favored language of developers. As youll see here, CompileIt! 2.0 overcomes nearly all of the objections to using HyperTalk as a serious development environment.
Objection #1: HyperTalk is too slow. You pay a price for convenience and ease of use. HyperTalk 1.2.x is an interpreted language. When messages are caught by a handler, the words in the handler script are turned into tokens that are interpreted by HyperCard. In HyperTalk 2.0, the handler scripts are turned into tokens and then compiled into machine language. Thus HyperCard 2.0 is faster once the handler scripts are compiled (memory permitting though since compiled handlers are purged to make room for new ones). Still, most of us dont think that this is enough. With CompileIt! 2.0 you can boost the speed of most if not all of your handlers.
Objection #2: You cant create a stand-alone application with HyperCard. CompileIt! doesnt provide a solution for this problem, but there are other products appearing in the market that claim they can do this such as SuperCard which can save projects as stand-alone applications. Unless you are really short on disk space, you shouldnt care about this that much anyway since nearly everyone has HyperCard.
Objection #3: HyperTalk doesnt have complete access to the Macintosh ROMs. XCMDs and XFCNs provide support for virtually any ROM routine. This excuse is usually used by people that cant or wont program in C or Pascal. Creating externals with CompileIt! from your scripts is as easy as writing them in HyperTalk. Extensions added by CompileIt! make toolbox support much easier.
Objection #4: Protection of sensitive program code is difficult in HyperCard. Even though you can protect a stack, there are ways to break that protection. Compiled code doesnt allow users to readily view the source code. With CompileIt! you can protect your valuable work by compiling sensitive code.
CompileIt! was designed to:
° Speed up HyperCard scripts
° translate HyperTalk scripts into 68000 machine language resulting in XCMDs and XFCNs that can be used by any HyperCard script.
° provide extensions to HyperTalk
Although using CompileIt! comes fairly easy, it is highly recommended that you are experienced with HyperTalk scripts. You should be familiar with handlers, messages, and properties before using CompileIt!.
Its very tempting to just paste in a script and begin compiling. The CompileIt! 2.0 program consists of a HyperCard stack that allows you to paste your script from the clipboard and then compile. Its very interesting to note that CompileIt! 2.0 is much faster than earlier versions of CompileIt! Thats because CompileIt! 2.0 has been compiled with CompileIt! The compiling engine consists entirely of resources and only a single line of code that ties the HyperCard interface to the engine. This means that CompileIt! 2.0 can be totally customized to fit the developers needs - even going as far as creating a stand-alone application to hold it or moving it into other environments like Microphone II v3. All that is required to use the engine is a subset of the HyperCard 1.x XCMD interface.
Before using CompileIt! there are a few things that should be understood about the way CompileIt! works. The first part of CompileIt!s 200 page manual helps you get started with a sample script. Experienced HyperTalk scripters will be able to get started quickly by going through about 7-10 pages of CompileIt! basics. Not every script can be made to run faster by compiling. Scripts that deal with HyperCard structures (that is menus, buttons, fields, cards, etc.) will not go much faster. They must still pass messages to HyperCard routines that still run the same speed. Get, Put, all forms of Repeat, Next (repeat), all forms of If-Then-Else, Abs, Add, Atan, Average, CharToNum, Cos, Delete, Divide, Exit, Exp, Exp1, Global, Length, Ln, Ln1, Log2, Min, Max, Multiply, Number(chunks), NumToChar, Offset, Param, Params, ParamCount, Pass, Random, Result, Return, Round, Sin, Sqrt, Subtract, Tan, Trunc, HyperTalk operators: Div, Mod, +, -, *, &, &&, , ¾, =, , <, >, And, Or, Not, Is Not, Is, /, ^, Constants, Ordinals, and Toolbox calls will all run faster after compiled with CompileIt!
You may need to optimize existing scripts to be sure that they dont use too many callbacks to HyperCard. For example, the statement put x into y in the script below will make the routine run faster than if x was used throughout the script instead of y. Otherwise, the compiler would have to generate code to convert the string variable x each time it is used. Instead, the conversion from string x to local variable y is done only once. It is helpful to keep in mind that HyperTalk does a lot of conversion for you. By minimizing the amount of conversion that has to be done, the routine can run faster. Unlike HyperCard, where all variables are strings, variables can be declared at the start of a compiled handler. CompileIt! allows many more data types to be declared than are available in HyperCard. Short integers, long integers, Pointers, Handles, P-Strings (including short P-Strings), 0-terminated strings (call these HyperCard strings), OSTypes, Boolean, Character, Floating point (12-byte SANE values), and Records (default is 32 bytes but user can specify any size).
-- calculate ( y)
-- by subtracting odd numbers
function squarroot x
put x into y
put 0 into ans
put 1 into oddint
repeat while y 0
subtract oddint from y
add 1 to ans
add 2 to oddint
Normally, Apples SANE routines will be used to perform all of CompileIt!s calculations, although SANE can be turned off to force some variables to integer type. Several techniques can be used to tell CompileIt! that a particular value is floating point - putting 0.0 into a variable to initialize it, adding ^1 after the variable, or declaring it as floating point using shared variables. The manual discusses the pros and cons of using SANE vs. integer math.
Except for the routines specifically marked as NOT IN ROM in Inside Macintosh, all procedures and functions are included from Inside Macintosh vol. I-V. Also, selected NOT IN ROM routines are included such as the High-Level file manager and Print Manager (NOT IN ROM routines are included based on user demand). Many of the record structures and low-memory globals are also included. Many (but not all) of the Inside Mac VI routines and record structures are also included. CompileIt!s Custom Symbol Edit card allows users to add additional record structures, low-memory globals, user defined constants, direct calls to other external commands (avoids a slow text callback), and other symbols on their own. Using these calls requires you to convert Inside Macintosh Pascal notation to HyperTalk/CompileIt notation. For example, a common procedure from Inside Macintosh would be: Procedure DrawString (S: Str255); the HyperTalk/CompileIt! equivalent would be: DrawString anystring. Youll also have to setup record structures to match those in Inside Macintosh. Fortunately, CompileIt! supplies the property names for many of the common types used in Inside Macintosh. If you are not an experienced programmer, it will take some study of the CompileIt! manual sections on programming with the toolbox. Experienced programmers wont have any trouble with it.
The process of compiling a script begins by copying your script into the clipboard. Open CompileIt! and click on the Enter New Script button. Select the destination stack where CompileIt! will put the external code. CompileIt! will use the name of the handler of the script. That is, if the script started with on mouseup then the name of the external would be mouseup and it would respond to a mouseup message. When you click on the CompileIt! button, the compile begins. It is highly recommended that users not use system messages as XCMD or XFCN names since they tend to get executed when users least expect them too. Better to use On Foo or some such. Also, the word On results in an XCMD while the word Function results in an XFCN.
An equally great part of the CompileIt! XCMD Development System is the DebugIt! source level debugger. When you compile a script with DebugIt! turned on, debugging code is added to your external function. When you execute your compiled external, the DebugIt! window will open and execution will halt before the first line is executed. Now you can set breakpoints, view variables, and single step through the external. This gives you as much flexibility in debugging your external as you could ask for. You may find it interesting that DebugIt! is not tied to HyperCard. Externals with DebugIt! attached can be run in just about any environment that supports even a limited subset of the HyperCard 1.x XCMD interface (FoxBase, Microphone II v3, XLINK, and SuperCard are all good examples).
CompileIt! can be used to create xWindoids (external windows) for HyperCard 2.0. CompileIt! simplifies the code you need to write to support an xWindoid by treating events like system messages. HyperCard automatically tells xWindoids about various system events that apply to them such as mouseDowns, updates, menubar clicks, etc. xWindoids are a new feature of HyperCard 2.0.
CompileIt! also works with SuperCard 1.5. Since CompileIt! is shipped as HyperCard 1.2 format, SuperCard users will need to convert to SuperCard format. An appendix in the CompileIt! manual spells out what to do and what to be aware of when using SuperCard and CompileIt!
There are several reasons to go with CompileIt! The price is right at $99, and there are no fees for distribution of your compiled externals. The compile process is a snap, but you should have a good knowledge of HyperTalk. CompileIt! is a great way to speed up and protect sensitive scripts.
CompileIt! 2.0 is distributed exclusively by:
P. O. Box 232019
Pleasant Hill, CA. 94523
Phone: 800--888-7667 or 415-943-7667
Price: $99 (working model: $10.00 compiles scripts up to 10 lines long. The Working Model includes a $10 rebate towards the purchase of CompileIt! 2.0).
Requires: Any Macintosh that can run HyperCard. Supports all versions of HyperCard, including 2.0, and SuperCard 1.5. A moderate level of programming ability is required.
Not copy protected and no runtime fees or licenses are required to distribute externals created with CompileIt!