* geesh/repl.scm (run-repl): Add optional port parameter.
* scripts/geesh.in: Add '--command' and '--stdin' flags, and if
neither flag is provided, treat the first argument as a file to
interpret.
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/word.scm (expand-word): Change the 'split?' keyword argument
to 'output', accepting one of 'fields', 'string', or 'pattern'.
(word->qword): Update calls.
* geesh/eval.scm (eval-word): Same as 'expand-word' above.
(eval-redir): Update call.
(eval-sh): Update calls.
* 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/shell.scm (sh:set-redirects): New public function.
* geesh/eval.scm (eval-sh): Use it to handle 'exec' specially when
called with redirects but no arguments.
This was simply a mistake.
* geesh/shell.scm (sh:substitute-command): Leave 'current-input-port'
and 'current-error-port' alone.
* tests/shell.scm: Remove tests that check that input and error gets
ignored during substitutions.
Instead of saving and restoring redirects manually, if we let them all
be parameters (like 'current-input-port'), we can use 'parameterize'
and make Guile take of this for us. As a side-effect of this change,
redirect errors get handled.
* geesh/shell.scm (save-and-set-redirect): Rename this...
(redir->parameter+port): ...to this and change the return value to be
a pair consisting of a parameter and a port.
(restore-saved-port): Remove function.
(sh:with-redirects): Use 'parameterize' to effect redirects rather
than updating them and restoring them manually.
There are two issues that arise due to output port buffers and
forking. If we run Scheme code in a child process, we need to avoid
copying buffered output into the child process. Otherwise, the
buffered output could be written twice. If we run non-Scheme
code (i.e., exec), we need to flush the ports to ensure proper
sequencing of writes since the non-Scheme code will not know about the
buffered output and will write its output before the buffer gets
flushed.
* geesh/shell.scm (exec-utility): Flush all ports before forking.
(%subshell): Ditto.
* geesh/word.scm (split-fields): Move handling of list words into
'wedge-apart' so that they get handled in recursive calls.
* tests/word.scm: Add a test for this.
* geesh/word.scm (split-fields): Make an empty string yield zero
fields (an empty list).
* tests/word.scm: Update tests and add tests to make sure that quoted
empty strings are preserved.
* geesh/word.scm (split-fields): Handle a special '<sh-at>' qword
form, so that a quoted '$@' reference can still be split.
(argument-separator): New function.
(remove-quotes): Handle the '<sh-at>' form when it should not be
split. This requires knowing how to concatenate arguments, so add an
'ifs' parameter.
(expand-word): Pass 'ifs' to 'remove-quotes'.
We used to model 'IFS' as a character set, but when handling special
parameters, the order of the characters matters. Since it is also an
environment variable, it makes sense to treat as a string (rather than
a list).
* geesh/word.scm (split-fields): Treat 'ifs' as a string instead of a
character set.
(expand-word): Get 'ifs' from the environment if available or use a
default string otherwise.
* 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.
* geesh/shell.scm (swap-and-shift-pairs): New function.
(make-pipes): New function.
(plumb): New function.
(sh:pipeline): New public function.
* tests/shell.scm: Test it.
Before, we were using raw file descriptors. This worked okay, but
there was interference caused by port buffering. Doing everything at
the port level avoids this problem, and has the added benefit of
allowing one to use the 'current-*-port' parameters with the shell
module (in a limited way, but there is room for improvement).
* geesh/shell.scm (*fd-count*): New variable.
(fd->current-port): New function.
(install-current-ports!): New function.
(exec-utility): Use it to set up file descriptors.
(save-and-install-redirect!): Rename this...
(save-and-set-redirect): ...to this and modify the current port
parameters instead of raw file descriptors.
(restore-saved-fdes!): Rename this...
(restore-saved-port): ...to this.
(sh:with-redirects): Adjust to use the renamed functions.
(sh:substitute-command): Parameterize the current ports directly
instead of using redirects.
* tests/shell.scm: Add tests to check if port buffers cause problems.
Timothy Sample