REBOL 3 Concepts: Tour: Paths

Pending Revision

This document was written for R2 and has yet to be revised for R3.

OLD DOCS

This section is obsolete and being replaced. It is kept only as a source for new content.

If you are using files and URLs, then you are already familiar with the concept of paths. A path provides a set of values that are used to navigate from one point to another. In the case of a file, a path specifies the route through a set of directories to the location of the file. In REBOL, the values in a path are called refinements.

A slash (/) is used to separate words and values in a path, as shown in the following examples of a file path and a URL path:

%source/images/globe.jpg

http://www.rebol.com/examples/simple.r

Paths can also be used to select values from blocks, pick characters from strings, access variables in objects, and refine the operation of a function, as shown in the following examples:

USA/CA/Ukiah/size (block selection)
names/12          (string position)
account/balance   (object function)
match/any         (function option)

The print function in next example shows the simplicity of using a path to access a mini-database created from a few blocks:

towns: [
    Hopland [
        phone #555-1234
        web   http://www.hopland.ca.gov
    ]

        Ukiah [
        phone #555-4321
        web   http://www.ukiah.com
        email info@ukiah.com
    ]
]

print towns/ukiah/web
http://www.ukiah.com