15.4.962  src/lib/src/path-utilities.pkg

## path-utilities.pkg

# Compiled by:
#     src/lib/std/standard.lib

# Various higher-level pathname and searching utilities.

###                   "There is no royal road which leads to geometry."
###
###                                          -- Euclid (c 323-283 BCE)


package   path_utilities
: (weak)  Path_Utilities                                        # Path_Utilities        is from   src/lib/src/path-utilities.api
{
    package p =  winix__premicrothread::path;                   # winix__premicrothread is from   src/lib/std/winix--premicrothread.pkg
    package f =  winix__premicrothread::file;

    fun exists_file prior path_list file_name
        =
        iter path_list
        where
            fun check s
                =
                if   (prior s   )   THE s;
                              else   NULL;   fi;

            fun iter []
                    =>
                    NULL;

                iter (p ! r)
                    =>
                    case (check (p::make_path_from_dir_and_file { dir=>p, file=>file_name } ))
                      
                         NULL   =>  iter r;
                         result =>  result;
                    esac;
            end;
        end;

    fun all_files prior path_list file_name
        =
        iter (path_list, [])
        where
            fun check s
                =
                if   (prior s   )   THE s;
                              else   NULL;   fi;

            fun iter ([], l)
                    =>
                    reverse l;

                iter (p ! r, l)
                    =>
                    case (check (p::make_path_from_dir_and_file { dir=>p, file=>file_name } ))
                      
                         NULL  =>  iter (r, l);
                         THE s =>  iter (r, s ! l);
                    esac;
            end;
        end;

    fun file_exists s
        =
        f::access (s, []);

    file_file  =  exists_file  file_exists;
    find_files =  all_files    file_exists;

};


## COPYRIGHT (c) 1997 Bell Labs, Lucent Technologies.
## Subsequent changes by Jeff Prothero Copyright (c) 2010-2015,
## released per terms of SMLNJ-COPYRIGHT.