st

Section: User Commands (1)
Updated: local
Index Return to Main Contents

NAME

st - a Little Smalltalk

SYNOPSIS

st [options] [files]

DESCRIPTION

st is an interpreter for a Smalltalk-like language. For a complete description of the language accepted by the interpreter see the user manual. Options accepted by the command are as follows:

-a: If the -a option is given statistics on the number of memory allocations will be displayed following execution.
-ddigit: If the digit is zero only those results explicitly requested by the user will be printed. If 1, the values of expressions typed at the keyboard will be displayed (this is the default). If 2, the values of expressions and the values assigned in assignment statements will be displayed.
-f: The -f option indicates fast loading should be used, which loads a binary save image (see ``)s'' below) for the standard library.
-g: The next argument is taken to be the name of an additional library stored in the system library area. The library is loaded following the standard prelude, just as if a ``)g'' directive were given at the beginning of execution (see below).
-l: The next argument is taken to be the name of a file containing a binary image saved using the )s directive (see below). This binary image is loaded prior to execution.
-m: Do not perform fast loading. (Used when fastloading is the default).
-n: The -n option, if given, suppresses the loading of the standard library. As this gives you a system with almost no functionality, it is seldom useful except during debugging.
-r: The next argument is taken to be the name of a file of Smalltalk commands. The file is included prior to execution, just as if a ``)r'' directive were given at the beginning of execution (see below).
-s: In normal operation, at the end of execution the number of reference count increments and decrements is printed just prior to exit. In the absence of cycles these two figures should be equal. Since cycles can cause large chunks of memory to become unreachable, and seriously degrade performance, this information is often useful in debugging. The -s option, if given, suppresses the printing of this information.

The files, if given, must contain class descriptions. Consult the reference manual for the syntax for class descriptions. The classes defined are included along with the standard library of classes before execution begins.

Once execution begins, the cursor will tab over 8 spaces to indicate that a command can be entered. A command consists of a valid Smalltalk expression, without a terminating period. As each expression is entered it is executed by the Little Smalltalk interpreter, and the results displayed.

The following system directives can be entered in place of commands:

)e filename: Edit the named file, which must contain only class descriptions. The Little Smalltalk system will suspend, leaving the user in an editor for making changes to the named file. Upon exiting the editor, the named file will automatically be included, as with the )i directive (below). The editor chosen by this command is taken from the variable EDITOR in the user's environment.
)g filename: Search for a file with the given name in the system library area. If found, load the library in with the users classes. This is useful for creating libraries of commonly used classes which are not part of the standard prelude, such as classes for statistics applications or for graphics.
)i filename: Include the named file. The File must contain one or more class descriptions. The class descriptions are parsed, and if syntactically legal new instances of class Class are added to the Smalltalk system.
)l filename: Load a saved binary environment. The file must have been previously created using the )s directive (below). The values of all variables are overridden.
)r filename: Read the named file. The effect is just as if the lines in the file had been typed at the keyboard. The file cannot contain class descriptions.
)s filename: Save the current environment in the named file. The values of all variables will be saved, and can later be restored using the )l directive (above).
)!string: Execute the string following the exclamation point as a Unix command.

Author

Tim Budd, Department of Computer Science, Oregon State University

Bugs

Not all the Smalltalk-80 Language described in the Blue Book is supported; see the user manual for details. (Smalltalk-80 is a trademark of Xerox Corporation).

This document was created by man2html, using the manual pages.
Time: 18:59:30 GMT, September 30, 2022