When a browser requests a URL that refers to a directory, web server usually
redirect the browser to the same URL with a trailing '/' added, if one was not
already present. This is to prevent relative links in the returned document
from being interpreted relative to the parent directory instead of the current
document. This type of redirection was missing in gf -server.
By adding a header
Access-Control-Allow-Origin: *
to the HTTP responses, web browsers are informed that it is OK to call the
services from web pages hosted on other sites.
This is apparently supported in most modern browsers, so it should no longer
be necessary to resort to JSONP.
See https://developer.mozilla.org/en-US/docs/HTTP/Access_control_CORS
The package network-2.4.1.1 thoughlessly introduced a backward incompatible
change to the function Network.URI.unEscapeString, see
f2168b1f89
This also affects the function Network.Shed.Httpd.queryToArguments, which is
used in GFServer.hs.
To remain compatible with older and newer versions of the network package,
we need to stay clear of queryToArguments and unEscapeString. A replacement
function has been added to server/URLEncoding.hs.
Also in Commands.hs: be explicit about things imported from the PGF library
that are not in the public API.
Also a couple of haddock documentation fixes.
When compiling a grammar containing characters that are not supported in the
current locale, warning messages could cause GF fail with
hPutChar: invalid argument (Invalid or incomplete multibyte or wide character)
With this quick fix, warning messages that can not be displayed are silently
truncated instead, and compilation continues.
This should prevent errors like
Internal error in Compute.ConcreteNew:
Applying Predef.drop: Expected a value of type String, got VFV [VString "gewandt",VString "gewendet"]
The sequence operator (x+y) was implemented by splitting the string to be
matched at all positions and trying to match the parts against the two
subpatterns. To reduce the number of splits, we now estimate the minimum and
maximum length of the string that the subpatterns could match. For common
cases, where one of the subpatterns is a string of known length, like
in (x+"y") or (x + ("a"|"o"|"u"|"e")+"y"), only one split will be tried.
The parser works on raw byte sequences read from source files. If parsing
succeeds the raw byte sequences are converted to proper Unicode characters
in a later phase. But the parser calls the function buildAnyTree, which can
fail and generate error messages containing source code fragments, which might
then containing raw byte sequences. To render these error messages correctly,
they need to be converted in accordance with the coding flag in the source
file. This is now done for UTF-8-encoded source files, but should ideally also
be done for other character encodings. (Latin-1-encoded files never suffered
from this problem, since raw bytes are proper Unicode characters in this case.)
+ Instead of "Internal error in ...", you now get a proper error message with
a source location and a function name.
+ Also added some missing error value propagation in the partial evaluator.
+ Also some other minor cleanup and error handling fixes.
It failed to delay table selection when the selector contains a run-time
variable, causing "gf: Prelude.(!!): index too large" instead.
Also:
+ Show better source locations on unexpected errors, to aid bug hunting.
+ Removed unused SourceGrammar argument to value2term.
The work done by the partial evaluator is now divied in two stages:
- A static "term traversal" stage that happens only once per term and uses
only statically known information. In particular, the values of lambda bound
variables are unknown during this stage. Some tables are transformed to
reduce the cost of pattern matching.
- A dynamic "function application" stage, where function bodies can be
evaluated repeatedly with different arguments, without the term traversal
overhead and without recomputing statically known information.
Also the treatment of predefined functions has been reworked to take advantage
of the staging and better handle partial applications.
