Using SPARQL's URI( ) fn w/PREFIX & suffix containing slashes? - uri

Question

I want to use a PREFIX to simplify URI creation. Will welcome any advice that helps me build a mental model of what PREFIX is doing in a SPARQL query - it doesn't seem to a simple key/value replacement.
Here are some examples of what have tried.
working
This works as expected and does what I want, except for not using a PREFIX.
SELECT * WHERE {
BIND ( URI("http:://www.foo.com/bar/01/grik/234") as ?s ) # (a) works fine
?s a ?o .
# Here (a) works as expected. I'm binding ?s to a specific URI
# for testing because otherwise it runs too long to debug my query logic.
}
LIMIT 10
My failed PREFIX attempts
My actual prefix URI fragment is longer but this example shows the idea.
I want to put the first part of the above URI, http:://www.foo.com/bar/, in a PREFIX and use 01/grik/234 as a suffix.
Variations of this return nothing or error out on URI composition:
PREFIX foo: <http:://www.foo.com/bar/>
SELECT * WHERE {
# I'm just running run one of these BIND statements
# at a time; listing all of them here for easier visual comparison.
# BIND ( URI(foo:01/grik/234) as ?s ) # (b) Lexical error. Encountered "/" after "grik"
# BIND ( URI(foo:"01/grik/234") as ?s ) # (c) Encountered " <STRING_LITERAL2> "\01/grik/234"\""
# BIND ( URI(foo:URI("01/grik/234")) as ?s ) # (d) Encountered "/" after "01"
# BIND ( URI(foo:ENCODE_FOR_URI("01/grik/234")) as ?s ) # (e) Encountered "/" after "01"
# BIND( URI(foo:ENCODE_FOR_URI("01/grik/234")) as ?s ) # (f) WARN URI <http:://www.foo.com/bar/ENCODE_FOR_URI> has no registered function factory
?s a ?o .
}
LIMIT 10

Answer 1

You're trying to use a IRI in its prefixed name form. The W3C SPARQL recommendation contains the following section
4.1.1.1 Prefixed Names
The PREFIX keyword associates a prefix label with an IRI. A prefixed name is a prefix label and a local part, separated by a colon
":". A prefixed name is mapped to an IRI by concatenating the IRI
associated with the prefix and the local part. The prefix label or the
local part may be empty. Note that SPARQL local names allow leading
digits while XML local names do not. SPARQL local names also allow the
non-alphanumeric characters allowed in IRIs via backslash character
escapes (e.g. ns:id\=123). SPARQL local names have more syntactic
restrictions than CURIEs.
Given that / is a non-alphanumeric character, the most important part here is
SPARQL local names also allow the non-alphanumeric characters allowed
in IRIs via backslash character escapes (e.g. ns:id\=123).
Long story short, your query should be
PREFIX foo: <http:://www.foo.com/bar/>
SELECT * WHERE {
BIND ( URI(foo:01\/grik\/234) as ?s )
?s a ?o .
}
LIMIT 10