Compiler directives

Certain keywords, beginning with `%', modify the action of the  compiler
when  present in a script.  These are called `compiler directives'.  The
directives currently available are as follows.

%list %nolist
 If the `/list' feature is  enabled  (switched  on  and  off  by  /list,
/nolist  at  command  level) the compiler echos the source to the user's
terminal during compilation of a Miranda script.  The directives  %list,
%nolist  may be placed in a file to give more detailed control over this
behaviour.  If the compiler is in an  echoing  state  then  encountering
`%nolist'  causes  it  to  cease  echoing from that point onwards in the
source, until the next occurrence of '%list' or the end  of  the  source
file  in  which  the  directive  occurs, whichever is the sooner.  These
directives may occur anywhere in a script and  have  no  effect  on  the
semantics  (i.e.   they  are  just  like  comments,  apart from having a
side-effect on the lex analyser).

If  the  `/list' feature of the compiler is not enabled these directives
are ignored.  Since the default state of the compiler is  now  `/nolist'
these  directives are of marginal value and retained only for historical
reasons.

%insert
 A directive of the form
        %insert "pathname"
may occur anywhere in a Miranda script, and is textually replaced by the
contents  of  the file "pathname" during lexical analysis.  The pathname
must be given as a literal string, enclosed  in  double  quotes.   (Most
uses of this directive are now better handled by %include, see below).

If the %insert directive is textually indented in the file in  which  it
occurs, the whole of the inserted text will be treated as being indented
by the same amount as the initial `%' of the directive.

Insert  directives  may be invoked recursively, to a depth limit imposed
by the operating system, typically about 16, which should be enough  for
any   reasonable   purpose.    Note  that  the  pathnames  are  resolved
statically, not dynamically, so that the meaning of an %insert directive
is computed relative to the file in which it occurs, NOT relative to the
directory from which the compiler was invoked.

The use of static rather than dynamic pathname resolution is a departure
from  normal  UNIX conventions (both the `C' compiler and the UNIX shell
resolve pathnames dynamically) but is much more convenient in practice.

Note that if the subject of an %insert directive is a  complete  Miranda
script  it  is  always better to use %include (see manual section on the
library mechanism), since this  avoids  needless  recompilation  of  the
definitions  of the subsidiary script.  The use of %include also imposes
a hierarchical scope discipline, and is more  likely  to  lead  to  well
structured code.

A point to beware of when using %insert is that unlike %include, it does
NOT add a missing `.m' extension to its pathname argument automatically.
This is because the argument file may contain an arbitrary piece of text
(e.g.   an expression or a signature) and need not be a complete Miranda
script, so it would be inappropriate to insist that it is  pathname  end
in `.m' in all cases.

%include %export %free
 These directives control the  identifier  bindings  between  separately
compiled  scripts.  See separate manual entry on `the library mechanism'
for details.

