Bug Reports

If you find a bug, please report it to mira-bugs at the domain
        miranda.org.uk
First check the list below, however, in case it is already known.   Also
check  the  downloads  section  of  the website to see if there is a new
version of Miranda in which your bug may be fixed.  When sending  a  bug
report,  please  state the version number of your Miranda system and the
platform that it is running on.  Send your report in  plain  text  -  no
html, no attachments please.

Bug reports are valued but will not always receive an individual  reply.
Suggestions  for improvements to the Miranda language or system are also
welcome.

Note on error messages:-
 The error messages from the Miranda system are mostly self explanatory.
Note  however  that  any  message  of  the  form  "impossible event ..."
indicates that an unexpected internal error has occurred.   Messages  of
this form should always be reported as bugs.  Any segmentation faults or
core dumps should also be reported, as these too should not occur.

List of known bugs, deficiencies, and unimplemented features

If there is not enough heap to compile the current  script,  mira  exits
after reporting this fact.  The fix is to increase the heap size:
        mira -heap N [filename]
where N is a bigger number than you had before.

There ought to be a directive  which  can  be  placed  in  a  script  to
suppress or modify the automatic inclusion of the standard environment.

It is not currently permitted  to  give  a  type  specification  for  an
identifier  defined  locally,  as  part of a where clause.  That is (see
formal syntax) `spec' is not allowed after where.

When abstract objects are tested for equality or order (under <, <= etc)
the  result is that obtained by applying the operation to the underlying
representation type.  In some cases this will be what you want,  but  in
others it will be wrong - there ought to be a way of controlling this.

The standard input cannot be accessed both as a list of characters (with
$-)  and  as  a  list of values (with $+) at the same time.  If $+ is in
use, an occurrence of $- will evaluate to [], and vice versa.   This  is
not referentially transparent - uses of $+ and $- ought to share data.

Scripts with multiple occurrences of $+  also  behave  opaquely  -  each
occurrence  of $+ reads from the terminal independently, and they do not
share data with each other.  (Multiple occurrences of  $+  in  a  single
command-level expression behave transparently, however.)

There is a subtle issue concerning `show' and %export.  If you define  a
function  which, internally, uses `show' on an object of algebraic type,
and then %export that function to another scope, the format used by  the
`show'  depends  on  the  status of the algebraic type in the NEW scope.
Thus if the type has been aliased the  new  constructor  names  will  be
used,  and  if the algebraic type is no longer in scope, it will show as
"<unprintable>" (this latter case can arise if an abstract type based on
the  algebraic  type  is  exported, and one of the signature identifiers
invokes  `show'  on  the  base  type).   Although  this   behaviour   is
defensible,  it might be better for each use of `show' at algebraic type
to be frozen to use the constructor names in the scope where it  occurs.
[An analogous issue arises with `readvals'.]

Implementation restrictions not mentioned elsewhere in  the  manual:-  A
shell  command  called from mira using `!' is limited to 1024 characters
in length after any implied expansions (eg of `%') have been  performed.
The  same  restriction  applies  to  the  result of expanding out a `/e'
command.  The pathnames of Miranda scripts are limited to 200 characters
in  length,  including  the  `.m'  extension.   The  name  of the editor
supplied for the `/e' command, and the absolute pathnames of the miralib
directory,  and  of  the user's home directory, are also each limited to
200 characters in length.  The name of a Miranda script may not  contain
spaces (but directory names with spaces are allowed in pathnames).