* geesh/environment.scm (*return-tag*): New variable.
(call-with-return): New public function.
(sh:return): New public function.
(*atexit*): New variable.
(*exiting?*) New variable.
(set-atexit!): New public function.
(sh:exit): New public function.
* geesh/repl.scm (run-repl): Call sh:exit at the end of a script.
* geesh/shell.scm (sh:exec-let): Use call-with-return for functions.
* geesh/built-ins/dot.scm (main): Use call-with-return.
These names are too common, and it will be even worse with 'exit'
and 'return'.
* geesh/environment.scm (break): Rename this...
(sh:break) ...to this.
(continue): Rename this...
(sh:continue) ...to this.
* geesh/built-ins/break.scm (main): Update call.
* geesh/built-ins/continue.scm (main): Ditto.
* geesh/environment.scm (*options*): New variable.
(getopt): New public function.
(setopt!): New public function.
(*option-names*): New public variable.
(*option-letters*): New public variable.
Instead of passing around references to the environment, just treat it
as a global. The old way was just the remains of an idea to make the
environment immutable and keep the interpreter from manipulating any
global state. By making everything global and mutable, we will have
less impedance mismatch with POSIX going forward.
The following changelog is only a sketch, since nearly every function
has changed.
* geesh/environment.scm: Replace this module with one that treats the
environment as a global resource.
* tests/environment.scm: Delete file.
* Makefile.am: Remove it from the list of tests.
* geesh/shell.scm, geesh/eval.scm, geesh/repl.scm, geesh/word.scm,
geesh/built-ins/break.scm, geesh/built-ins/continue.scm,
geesh/built-ins/echo.scm, geesh/built-ins/export.scm,
geesh/built-ins/false.scm, geesh/built-ins/read.scm,
geesh/built-ins/readonly.scm, geesh/built-ins/set.scm,
geesh/built-ins/true.scm, geesh/built-ins/unset.scm: Remove 'env'
parameters and use the new environment module.
* .dir-locals.el: Update indentation of functions that no longer take
an 'env' parameter and add with-arguments, with-environ, and
with-variables from the new environment module.
* tests/shell.scm, tests/word.scm: Update environment creation and
manipulation in tests.
* geesh/environment.scm (<variable>): New record type.
(make-environment): Initialize variables as records.
(var-ref): Extract value from record.
(set-var!): Inject value into record and throw an error if variable
is read-only.
(set-var-export!): New public function.
(set-var-read-only!): New public function.
(environment->environ): Only include exported variables.
* geesh/environment.scm (delete-environment-vars!): New public function.
(delete-environment-functions!): New public function.
* geesh/built-ins/unset.scm: New file.
* Makefile.am: Add it.
* geesh/built-ins.scm: Enable 'unset'.
* geesh/environment.scm (<environment>): Add an 'arguments' field.
(make-environment): Add an optional 'arguments' parameter.
(with-environment-arguments): New public function.
.dir-locals.el: Indent it nicely.
* geesh/environment.scm (<environment>): Add a 'functions' field.
(make-environment): Initialize it to the empty list.
(environment-function-ref): New public function.
(define-environment-function!): New public function.
Instead of using an environment variable named '?', we will use a
special environment field called 'status'. This lets us get rid of a
lot of number-string conversions (since an environment variable has to
have a string value).
* geesh/environment.scm (<environment>): Add a 'status' field.
(make-environment): Set it to 0 by default.
* geesh/repl.scm (run-repl): Use new field in place of '?' variable.
* geesh/shell.scm (exec-utility, sh:and, sh:exec-let, sh:for, sh:not,
sh:or, sh:pipeline, sh:subshell, sh:substitute-command): Ditto.
* geesh/word.scm (parameter-ref): New function that handles both
special parameters (e.g., '?') and variables.
(parameter-ref*): Like 'var-ref*', but for 'parameter-ref'.
(word->qword): Replace 'var-ref' and 'var-ref*' with 'parameter-ref'
and 'parameter-ref*' respectively.