The system_pipe (aka "?") command creates a temporary file _tmpi containing
the input of the system command. It *both* appends _tmpi as an extra argument
to the system command line *and* adds an input redirection "< _tmpi". (It
also uses and output redirection "> _tmpo" to captures the output of the
command.)
With this patch, the _tmpi argument is no longer appended to the command line.
This allows system_pipe to work with pure filters, such as the "tr" commands,
but it will no longer work with commands that require an input file name.
(It is possible to use write_file instead...)
TODO: it would also be fairly easy to eliminate the creation of the _tmpi and
_tmpo files altogether.
Add proper type checking of course-of-values tables:
+ Make sure that all subterms have the same type.
+ Resolve overloaded operators.
Note though that the GF book states in C.4.12 that the "course-of-values
table [...] format is not recommended for GF source code, since the
ordering of parameter values is not specified and therefore a
compiler-internal decision."
The CF parser in GF.Grammar.CF assigns function names to the rules, but they
are not always unique, causing rules to be dropped in the follwing CF->GF
conversion. So a pass has been added before the CF->GF conversion, to make
sure that function names are unique.
A comment says "rules have an amazingly easy parser", but the parser looks
like quick hack. It is very sloppy and silently ignores many errors, e.g.
- Explicitly given function names should end with '.', but if the do not, the
last character in the function name is silently dropped.
- Everything following a ';' is silently dropped.
Trailing spaces caused the command line parse to be ambiguous, and
ambiguous parses were rejected by function readCommandLine, causing
the cryptic error message "command not parsed".
The only use of PGF.Tree outside the PGF library was in GF.Command.Commands,
and it was eliminated by using PGF.Expr directly instead.
PGF.Paraphrase still uses PGF.Tree.
This module should not be part of the public PGF library API, and it was only
used in GF.CompileToAPI, so the code was moved there. The module defined
constFuncs and syntaxFuncs, but only syntaxFuncs was used.
