cells when searching in the tree
Two tricks: represent lists of nodes as improper lists so singleton
lists don't allocate a cons and pass around two accumulators that
correspond to the hd & tl of a path, instead of cons'ing that up
into a list and them immediately taking it apart again
measurement: when starting up drracket with
collects/drracket/private/unit.rkt and then waiting for the colorer to
finish, and then inserting an open quote right before the first open
quote in the file (and waiting again for the colorer to finish)
creates 249000 cons cells before this change and 116000 after this
change
After a little more work, I'm pretty much convinced that this was
the wrong approach and that the splaying implementation should just
change to not allocate the paths into lists at all, thus removing
the other 116k cons cells. (I plan to get to this another day;
it should not be difficult now that I roughly understand how these
things work.)
I also looked into top-down splaying and found these notes to
be illuminating:
http://digital.cs.usu.edu/~allan/DS/Notes/Ch22.pdf
They essentially convinced me that we cannot use top-down splaying
here, since the "reassembling" stage requires moving some arbitrary,
unexplored subtree from a right-child to a left-child, and thus the
left-subtree-length cannot be updated properly.
This distinction is important after the introduction of chaperones and
impersonators, since accessing a key and accessing its corresponding value
may have different effects, and hash-keys should only trigger the former.
the errors that would be signalled by the body. also, remove
url-regexp from the exports (it was only recently added)
I believe this eliminates two of Eli's concerns:
- the contract is no longer so painful to read
- the performance is more reasonable.
Specifically, for the performance, here are the times I see to call
string->url on "http://www.racket-lang.org":
no contract: any/c
cpu time: 564 real time: 566 gc time: 3
weak contract: (-> (or/c string? bytes?) url?)
cpu time: 590 real time: 590 gc time: 3
strong, regexp-based contract:
(-> (or/c (not/c #rx"^([^:/?#]*):") #rx"^[a-zA-Z][a-zA-Z0-9+.-]*:") url?)
cpu time: 632 real time: 633 gc time: 5
This appears to be about a 10% slowdown for the regexp-based contract
over the weaker contract.
related to PR 12652
This convention makes it easier to deal with a set
of ".rkt" files that implement tests, while a `test'
module implements a `main'-like split for some of the
files.
The immediate symptom was that `(provide (all-defined-out))'
didn't work in a `module+'-based submodule, but there were
also non-submodule ways to expose the problem.
The `get-handle' method provides the underlying Cairo surface for
a bitmap, while the unsafe `make-handle-brush' function supports the
use of a Cairo surface as a `brush%'.
Also, add `racket/draw/unsafe/cairo-lib', which simplifies access
Cairo from external libraries. Documenting `racket/draw/unsafe/cairo'
might be better, but that's a lot more work.
The default is that hiniting is enabled, which causes some text
metrics (notably width) to be rounded to integer values, which makes
spacing more consistent. This default is backward-compatible. The
non-default 'unaligned mode refrains from rounding, which makes metric
information scale correctly and improves output for PS/PDF (such as
Redex output).
The `text' function from `slideshow/pict' defaults to
disabling hinting --- which is consistent with its default to combine
text instead of drawing character-by-character -- so slides and Redex
inherit the improvement.
* Get rid of the concept of `modspec': `getarg' now has `require' for
require specs and `module' for a module name (the latter is what all
previous uses of 'modspec except for ,require really needed); command
descriptions use "<require-spec>" and "<module>", documentation
adjusted as well.
* `module-name?' etc turn to `known-module' and `known-module-name',
with a saner behavior, and tests to keep it sane.
* This cleans up a lot of things. Two specific points: ,switch works
better with toplevel-defined modules (see the corresponding change in
the test suite), and also fixes PR 12148.
* Ensure that ,sh commands return void.
* Add tests for ,r with non-atomic require spec, and for use of $F in
,sh commands.
* Improved the test suite, including uses of `module+' so each file can
be run by itself to perform a subset of the tests.
pixel of space in between lines in DrRacket.
This change is based on Matthew's experience having a look
at the font setup on the three platforms.
He writes:
> * Mac OS X: the convention seems to be to add space between lines.
> TextEdit, for example, looks like DrRacket: the maze has spaces.
>
> (I can't find a font that makes the maze look right, actually, even
> if I adjust the line spacing.)
>
> * Windows: the convention seems to be that space is built into the
> font. DrRacket (and SirMail) draw lines more sparsely than Notepad.
>
> Perhaps consistent with the differing conventions, the height of
> "Courier New" at 11-pixel size is 14 on Windows, 13 on Mac OS X.
>
> * Unix: the convention seems to be to add space. DrRacket looks like
> the default Terminal and Text Editor programs on Ubuntu.
>
> The maze nevertheless looks right everywhere, because the glyphs
> extend an extra pixel above the declared bounding box!
This patch fixes the problem that the hole matcher may return an empty
list rather than a #f that gets sent to the caller of redex-match. I
re-ran the Redex tests and found no violations. However, I am not
confident that there isn't a more correct place to put this '() -> #f
replacement.
I will be immediately forwarding this push email to Robby to have him
check it.
- changed substitute to use closure-compilation
- added stress/perf test for templates
- updated minimatch with vector patterns
- split substitute into separate file, minimize dependencies
- do ellipsis optimization dynamically
- validate guides: check var indexes
It looks like run-teaching-program hasn't been touched in quite a while.
To begin with, the "rewrite-module" function used to add code to print
out values of non-define exprs, but this is no longer necessary. In fact,
the only thing that it does now is to discard "provide" statements, and
even this may be unnecessary. I rewrote big chunks of this (short) file
to introduce defines, eliminate unnecessary functions, and add stepper-
skip-completely annotations to the requires associated with teachpacks.
Also, it appears that the 'rep' argument to expand-teaching-program
was entirely superfluous; I removed it from the argument list, and also
from the three places in the main tree (deinprogramm, lang, and the stepper)
that call this function.
Let me know of any problems seen with teachpack requires....
* Modernize, improve, reformat, reorganize, etc.
* Use 'null as the default translation for json `null'. Add keyword
`#:null' arguments to control it, and a `json-null' parameter to
change the default. (Note that there is no ambiguity: symbols are
used in hash keys, and JSON restricts them to always be strings, so
`null' can never be a hash key.)
* Properly decode double \u-escape sequences (as UTF-16 surrogate
pairs).
* Add a keyword option to do more string encoding of all non-ASCII
characters.
* Rename `json->jsexpr' (and other way) to `string->jsexpr'. This is
because (a) after using it for a while I still can't remember which
side is which and a `string' in the name makes it clear, (b) it
follows the similar `xexpr' functions.
`port-success-k' is used in a single place, and instead of a simple
`lambda' expression it was used with (and ... (lambda ...)), which lead
to duplication of code. Instead, move the question into the
`regexp-loop' macro. (The compiled zo file is indeed smaller after this
change.)
Although th eoriginal idea was to distinguish "text" paths
from derived filesystem paths, practically everythign that accepts
a module path also accepts a path. Building the generalization into
`module-path?' makes it easier to support `submod' wrappers on paths,
and it seems to fix things rather than break them.
Before this commit, opening collects/drracket/private/unit.rkt required
about 17.5 megabytes of memory and after this commit, it is down to
about 15 megabytes.
The precise measurement I did was to create a frame and a scheme:text%
object in it, record the result of current-memory-use, open the file,
and record current-memory-use again.
For comparison, using a text:standard-style-list% object instead of
the scheme:text% requires only about 4.1 megabytes. One difference
being that there are about 3x more snips (10,204 vs 33,901 (after the
commit)), since we have one snip for each region that has a different
color in the scheme:text version, and the text:standard-style-list has
no colors and thus about two per line (there are 5006 lines in the
file).
The bug happens with n-ary uses of arithmetic operations that
have constant arguments but couldn't be constant-folded ---
maybe due to a divide-by-zero.
plots too small to render margin decorations (i.e. axis and tick labels) now render without them;
plots in frames now initially render with full detail
When uninitialized, turtles was giving a poor internal error.
Now it should tell the user to initialize. Also, added a note
in the docs about initialization.
Previously, sandbox creation used `gui?', which is the result of
`gui-available?' at the time that `racket/sandbox' is instanited.
This change makes sandbox behavior less sensitive tothe order in
which modules `require'd into a program are intiantiated.
The change depends on a new `sandbox-make-namespace' default
function for `sandbox-namespace-specs'. The new function uses
either `make-base-namespace' or `make-gui-namespace', depending
on whether the GUI library is available at that point.
A new `sandbox-gui-enabled' parameter can disable use of the
GUI library even if it is available.
The `gui?' binding is still exported for backward compatibility,
but it shouldn't be used anymore.
There are many SSL_() functions that produce return codes with more
information from SLL_get_error() and/or ERR_get_error(). Those need
to be grouped in an atomic section to ensure thread safety at the
level of Racket threads.
Using the functions on a port triggers renegotiation of the
connection, which s useful for cases such as a web server that
requires a certificate only for certain paths. This functionality
also allows better testing of the SSL library.
Read and write actions on an SSL port can trigger internal write
and read actions (i.e., the opposite direction). On the read side,
write pumping was performed too early before returning a "wait
for new input" event; SSL operations between the pumping and
return could trigger the need for pumping, but it never happened
because the socket was waiting for new input before taking any
new actions.
The problem would shows up specifically when Apache renegotiates
a connection to demand certificates from a client after first
determining the target of the request (i.e., when a certificate
is required ony for specific locations on the server).
Thenks to Sergey Pinaev, Timur Sufiev, and Neil Van Dyke.
them and use that to order 'raco setup'
The dep-list.rkt file contains code that reads .dep files
and computes the topological sort; this result is expected
to be copied over into setup-unit.rkt
Mostly for amusement, including the contrast between
the benefits of closure compilation for a host interpreter
versus the benefits for a host compiler.
The old implementation could cause deadlock by blocking on a semaphore
while waiting for the original place to run a callback, but a master
GC might be needed (and the blocked place wouldn't get the signal).
Beside fixing that problem, a potential memory leak is fixed in
calling an ffi funcition and having a Racket->C unmarshaling fail.
Also, the GC marking routine for a `place' value didn't reference the
place's underlying `place_obj' value.
The orange triangle is now updated after each turtle command. The erase
pen is now 2 pixels wide: before this, (draw 100) (erase 100) didn't
erase the line, but gave a grey line.
The eopl language is now racket-based rather than mzscheme-based. This
test-suite, which was originally distributed on the book's web-site has
been re-written in the new language. Changes include dropping all
drscheme-init.scm and top.scm files. Remaining files were renamed to
use the .rkt extension and edited to use the #lang syntax (instead of
modulue). Require and provide forms were changed to reflect racket's
syntax instead of mzscheme's (eg, only-in vs. only). Several
occurrences of one-armed ifs were changed to use when and unless. All
tests have been run successfully.