[_CDCSL_93-16_]<1>Cedar>release>PFS>PFSCanonicalNames.mesa

PFSCanonicalNames.mesa

Carl Hauser, August 9, 1988 5:54:24 pm PDT

DIRECTORY

IO USING [STREAM],

PFSNames USING [Component, PATH, Version],

Rope USING [ROPE];

PFSCanonicalNames: CEDAR DEFINITIONS

SHARES PFSNames

~ BEGIN OPEN PFSNames;

ROPE: TYPE = Rope.ROPE;

UnparseName: PROC[name: PATH]
RETURNS [fullFName: ROPE];

Canonical unparsing:

[/]component0/component1/.../componentComponentCount-1[/]

The first / is included if name.absolute; the last if name.directory.

UnparseComponent: PROC [component: Component] RETURNS [ROPE];

Canonical unparsing:

Rope.Cat[name, Unparse[version]]

bug: name unparsing should insert escape characters on /, ! (and, of course, the escape character).

UnparseVersion: PUBLIC PROC [version: Version] RETURNS [ROPE];

Canonical unparsing:

NIL, !H, !L, !*, !num as appropriate.

ParseName: PROC [name: ROPE] RETURNS [parsedName: PATH];

Parsing names in canonical form.

ParseComponent: PROC [name: ROPE, first: NAT ¬ 0] RETURNS [component: Component, next: NAT];

parses a component beginning at name[first] and returns that component; next = first + length of the parsed component.

bug: should interpret escape sequences.

ParseVersion: PROC [v: ROPE, first: NAT ¬ 0] RETURNS [version: Version, next: NAT];

parses a version beginning at name[first] and returns that version; next = first + length of the parsed version.

ParseNameFromStream: PROC [s: IO.STREAM] RETURNS [name: PATH];

A convenient way to read a whitespace-delimited name from a stream.

END.