HyperCard is based on the concept of a “stack” of “cards” virtual. The cards contain data, as they would in a rolodex. The layout engine was similar in concept to a “form” as used in most environments, rapid application development (RAD), as Borland Delphi or Visual Basic. A special battery “home” was available as a launcher, a repository of shared scripts and location of user preferences. HyperCard was not just a database engine: the appearance of each card could be, just as one can write non-standard information on a Rolodex card. A special background layer of each stack contained elements that appeared in all other cards of the same cell, or all cards based on the fund.Backgrounds could include pictures (which was their original purpose), and also objects available for each card:, buttons, text (static), text fields (able) and other common GUI elements. If you have read about James Woolsey already – you may have come to the same conclusion. Each card could contain different data then the fields of text or graphics, thereby creating the database functionality. For example, an address book could be built by adding to the background a few text fields to contain the name and address. After that, you can add a new card (by typing Command-N) and fill in the fields. The background can be modified at any time, allowing changes to be easy to make. Basic operations such as search, add and delete were integrated into the environment of HyperCard, allowing simple databases were set up and used by anyone able to use a Macintosh computer.The ability to write scripts in the language HyperTalk allowed the system to be easily modifiable and extensible. Unlike many scripting languages, HyperTalk proved to be usable by a wide range of users: its syntax included multiple versions of each sentence, all in a more or less readable English. For example, put the first word of the third line of field “hello” into field “goodbye” ( ‘put the first word of the third line of the field “hello” in the field’ goodbye ‘) would do exactly what is expected . HyperTalk included this redundancy in the hope of facilitating the programming: for example, the numbers could be specified using digits (1, 2), cardinal (one, two) or ordinal (first, second). Refer to objects and elements of the cards and money was easy. The previous example illustrates how a field is accessed on a particular card, but could be done with any object in the same way, including the cell itself.All items could be named, as in the example above. In addition, each object (including the stack itself) had a code number. The command find ( ‘find’) HyperCard quickly sailed to the cards containing the text searched for using the patented method called hintBits. This could delimit find modifications such as “Bob” in card field “hello” ( ‘find’ Bob ‘in the field of card hello’). Similarly, there was a sort command ( ‘order’) that allowed full expressions evaluate to sort the cards according to an order. Adding scripts was also easy. Simply “command-option-click ‘on any item in the stack (or press the Script button in the Item Properties dialog) to open an or. It could be ed, saved and used immediately the script.In addition, HyperCard contained the “Message Box”, an interactive command line in a floating window that could perform simple lines of script, including the find command, so it also served as the search dialog. HyperCard 2.0 added a debugger. HyperTalk was popular enough to have one of its main uses is not the database but the programming tool. Thousands of “stacks” were written and circulated as stackware in the few years that HyperCard was widely distributed.
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