Section 4.1. A Little Language


4.1. A Little Language

The "little language" philosophy, as represented by such computer languages as LOGO, Smalltalk, and Scheme, comes in various forms but the very words "little language" tell you most of what you need to know. Littleness can be a virtue in a number of ways. A little computer language can fit in a small space and be run by a small interpreter. A little computer language can be easy to learn, just because there's less of it to learn. A computer language is a tool to make tools, so the initial tool itself can be quite minimal, provided it has the power to make any other tools that may prove necessary.

All of these notions apply to AppleScript. AppleScript was to be easy for users to learn, so the less there was of it, the better. AppleScript appeared at a time when the idea of a computer with as much as four megabytes of random-access memory still felt rather strange and extravagant. To minimize expenditure of time and space resources, it had to compile with just a single pass. In these days of hundreds of megabytes of RAM and dozens of processes running simultaneously, it's easy to forget that AppleScript comes from a day when running more than one application at once on your Macintosh was a relatively new experience, and liable to tax the computer's resources to the utmost. At the time, AppleScript itself needed to be small simply to stay out of the way of other applications. The first version of AppleScript could load a scripting component instance and run a heavily recursive script in less than 300K of RAM.

And the purpose of AppleScript, after all, was to tell other programs to do things. Thus AppleScript itself could afford to be so minimal as to have little or no power of its own. AppleScript has minimal string-munging and number-crunching facilities, but then AppleScript is not intended for munging strings or crunching numbersit's made for driving applications, and they can munge the strings and crunch the numbers if need be.

So is AppleScript's littleness a virtue? Probably notat least, not any more. Thanks to Moore's Law and the passage of time, we no longer need AppleScript to be so tiny. Its small size certainly makes it easier to learn than, say, Perl (a language so big and so full of options and functions it can make your head swim), but it is not an easy language at all; on the contrary, it's tricky and quirky and needs a big book like this one to explain it. And if you're used to a full-fledged scripting language, AppleScript comes as something of a disappointment. Perl, for example, has some hundreds of built-in functions; AppleScript has about a dozen, and seems to be missing some extremely basic functionality. Perl has built-in support for powerful string manipulation, regular expressions, and trigonometry; AppleScript doesn't. Just as you don't miss the water until the well runs dry, the "little language" philosophy seems very cute just until you actually need to get something done. On the other hand, if you don't try to misuse it, AppleScript seems quite adequate, especially since it can now (under Mac OS X) avail itself directly of the power of Perl and other built-in Unix tools. As I said in Chapter 1, success may be simply a question of combining specialities appropriately.




AppleScript. The Definitive Guide
AppleScript: The Definitive Guide, 2nd Edition
ISBN: 0596102119
EAN: 2147483647
Year: 2006
Pages: 267
Authors: Matt Neuburg

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