INTERFACEThis tool provides control over the search path used by anM3PathTool ; IMPORT M3Extension, M3FindFile;
M3TK
application. The Define_Arg and TFile_Arg arguments are prefix
keywords, that is, any keyword that begins with a D or a T will
match and the value returned by M3Args.GetPrefixArg will be the text
of the keyword with the prefix removed.
The TFile_Arg may also occur zero or more time, and each occurrence
names a file that contains an explicit mapping of Modula-3 files to
directories, in the syntax specified in the M3DirFindFile interface.
For each occurrence, a file finder is generated
by a call to NEW(M3DirFindFile.TFinder).init.
The Define_Arg may occur zero or more times, and each occurrence specifies
a list of directories, in an OS-dependent syntax, in which to look for
Modula-3 files. Each instance generates an M3PathElemList.T, by a
call of M3PathElemOS.DecomposePath; the separate lists are then
concatenated in the order of occurrence of the associated arguments.
If neither of these arguments is given, a file named {\it m3path},
that is assumed to contain a search path, is searched for in the
current directory. If such a file is found an M3PathElemList.T
is generated by a call of M3PathFile.Read, otherwise a value
of NIL is returned.
In the latter two cases, the current working directory is prepended to
the search list by a call of M3PathDefaults.EnsureCurrentFirst and,
unless the NOSTD_Arg is set, the default library directories, as
given by M3Config.Pub(), are appended to the search list. A file
finder is then generated by a call to NEW(M3DirFindFile.Finder).init.
Finally, the finders are merged into a single instance with the merge
method. The merge process begins with the finder generated from the
Define_Arg arguments, if any, and then proceeds with the TFile_Arg
finders, in reverse order of occurrence.
The Check procedure checks for the above arguments and returns
the generated finder.
CONST Define_Arg = "D"; TFile_Arg = "T"; NOSTD_Arg = "NOSTD"; PROCEDURE Check(exts := M3Extension.All): M3FindFile.T;
Check for the tool arguments, set up the search path accordingly, and return a finder for the given set of extensions.
END M3PathTool.