proposal 'file string functions'

["ks" <klaus.schmid@xxxxxx>]

Model/Terminology:

  File == Path + Base

  Path=="" and Base=="" should be legal.
  This way a path or a base string can
  be handed over, wherever a file string
  is expected. A file may point to an
  existant or non-existant ordinary file
  or directory. Existancy, type, shortcut
  and profound syntax checking is not
  covered by these file string functions.
  For example type and existancy checking
  can be done with the present jed-function
  file_status. The proposed set of functions
  may replace the slang-functions path_*.

Elementary functions:

  Path= file_path( File)
  Base= file_base( File)
  Ext= file_ext( File)
  S= file_sans_ext( File)

Overloaded functions:

  Get path n levels higher and down to B1, B2, ... BM
  
    Path= file_path( File, n, B1, B2, ... BM)

  Get base n levels higher
  
    Base= file_base( File, n)

Examples:

  file_path( "d:[a.b]jedini.sl")  --> "d:[a.b]" on vms
  file_path( "c:\a\b\jedini.sl")  --> "c:\a\b\" on dos
  file_path( "/a/b/jedini.sl")    --> "/a/b/" on unix

  file_base( "/a/b/jedini.sl")           --> "jedini.sl"
  file_ext( "/a/b/jedini.sl")            --> ".sl"
  file_sans_ext( "/a/b/jedini.sl")       --> "/a/b/jedini"
  file_path( "/a/b/jedini.sl", 1, "c", "d")
  or file_path( "/a/b/", 1, "c", "d")    --> "/a/c/d/"
  file_base( "/a/b/jedini.sl", 2)
  or file_base( "/a/b/", 2)              --> "a"
  file_path( "/a/b/jedini.sl")+"c.sl"    --> "/a/b/c.sl"


I think these functions would be easier to read,
remind and use. What do you think?

Klaus