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To load files of Scheme code, use the procedure load:
Filename may be a string naming a file, or a list of strings naming multiple files. Environment, if given, is the environment to evaluate the file in; if not given the current REPL environment is used.
Syntax-table is no longer used and if supplied will be ignored.
The optional argument purify? is a boolean that says whether to
move the contents of the file into constant space after it is loaded but
before it is evaluated. This is performed by calling the procedure
purify (see Garbage Collection). If purify? is given
and true, this is done; otherwise it is not.
load determines whether the file to be loaded is binary or
source code, and performs the appropriate action. By convention,
files of source code have names ending in .scm, and files of
binary SCode have names ending in .bin. Native-code binaries
have names ending in .com. R7RS library files
conventionally end in .sld, .binld, and .comld
respectively.
If no file-name suffix is specified, load will choose a file by
trying different suffixes, preferring in order native-code binaries,
SCode binaries, and source files.
All file names are interpreted relative to a working directory, which
is initialized when Scheme is started. The working directory can be
obtained by calling the procedure pwd or modified by calling
the procedure cd; see Working Directory in MIT/GNU Scheme Reference Manual.
Loads the option specified by symbol; if already loaded, does
nothing. Returns symbol; if there is no such option, an error is
signalled. However, if no-error? is specified and true, no error
is signalled in this case, and #f is returned.
A number of built-in options are defined:
compressSupport to compress and uncompress files. Undocumented; see the source file runtime/cpress.scm. Used by the runtime system for compression of compiled-code debugging information.
formatThe format procedure.
See Format in MIT/GNU Scheme Reference Manual.
gdbmSupport to access gdbm databases. Undocumented; see the source
files runtime/gdbm.scm and microcode/prgdbm.c.
ordered-vectorSupport to search and do completion on vectors of ordered elements. Undocumented; see the source file runtime/ordvec.scm.
regular-expressionSupport to search and match strings for regular expressions. See Regular Expressions in MIT/GNU Scheme Reference Manual.
stepperSupport to step through the evaluation of Scheme expressions. Undocumented; see the source file runtime/ystep.scm. Used by the Edwin command step-expression.
subprocessSupport to run other programs as subprocesses of the Scheme process. Undocumented; see the source file runtime/process.scm. Used extensively by Edwin.
synchronous-subprocessSupport to run synchronous subprocesses. See Subprocesses in MIT/GNU Scheme Reference Manual.
In addition to the built-in options, you may define other options to be
loaded by load-options by modifying the file optiondb.scm
on the library path. An example file is included with the distribution;
normally this file consists of a series of calls to the procedure
define-load-option, terminated by the expression
(further-load-options standard-load-options)
Each thunk must be a procedure of no arguments. Defines the load
option named symbol. When the procedure load-option is
called with symbol as an argument, the thunk arguments are
executed in order from left to right.
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