FESI language extensions

Free EcmaScript Interpreter.
A JavaScript interpreter written in Java.

Language extensions - BasicIO, BasicIOw and BasicIOs

BasicIO, BasicIOw and BasicIOs

One of the BasicIO, BasicIOw and BasicIOs extension always loaded by the interactive interpreter program (but not if the interpreter is started by a user program, in which case it may be loaded if so desired). These extensions provide support for basic output (to the standard output), basic error message display, user prompt, file loading and program exit. The only difference between these packages is that the BasicIOw and BasicIOs use windows for the alert, prompt and confirm functions, while BasicIO just use the console. BasicIOw is for use with AWT based programs, and BasicIOs is for use with Swing based programs. Using the wrong version is likely to cause various disasters, as AWT and Swing do not fit together very well! When using the interactive interperter, BasicIOw is loaded via the -w option, and BasicIOs via the -s option.

The following global objects and routines are defined by BasicIO and BasicIOw:

alert (message): Write an [[alert]] message on the error stream.
confirm: Ask the user for a yes/no confirmation.
exit(status): Exit with the specified status (uses System.exit() , so the program is terminated!).
load (moduleName): Locate the module in the directories and jar/zip files of the property FESI.path or (if the property is not defined) in the classpath (possibly adding the extension ".es", ".esw' or ".js"). Load the module and evaluate its content at run-time.
prompt (query, [default]): Prompt the user for information, proposing the default string.
write(...): Write the parameters to the current output stream.
writeln(...): Write the parameters to the current output stream, followed by a new line.
document: An object for compatibility with JavaScript when expanding html files.
document.close(): Dummy routine for compatibility with JavaScript when expanding html files.
document.open(): Dummy routine for compatibility with JavaScript when expanding html files.
document.URL: Current file being processed (if defined by the interpreter).
document.write(...): Same as write .
document.writeln(...): Same as writeln .
window.alert (message): Same as alert .
window.confirm: Same as confirm.
window.prompt (query [default]): Same as prompt .

The documentand windowobjects are only used to ease writing scripts which can be tested in a browser as well as with FESI. They do not have any "window" or "document" functionality.

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Last update: 26 August 2003