add prefixes api

README.md

@@ -1,4 +1,5 @@
 # turtle parser
+
 <i>transforms a turtle string to a TurtleDoc</i>
 
 ## Work in progress
@@ -8,14 +9,16 @@
 - Comments are filtered
 
 ## Todo
+
 - error handling
-- iri as described in the spec
+- <s>iri as described in the spec</s>
 - cleanup
 - Jena like api
 
 ### Example
 
 #### Input
+
 ```turtle
    @prefix foaf: <http://foaf.com/>.
     [ foaf:name "Alice" ] foaf:knows [
@@ -26,7 +29,9 @@
     foaf:mbox <[email protected]>] .
 
 ```
+
 #### Output
+
 ```turtle
 <http://example.org/.well-known/genid#e162c9a7-52cf-4240-9359-b1b1f977f642> <http://foaf.com/name> "Alice"^^<http://www.w3.org/2001/XMLSchema#string>.
 <http://example.org/.well-known/genid#6955800d-16db-49f8-a614-b0cbea3d7fb2> <http://foaf.com/name> "Bob"^^<http://www.w3.org/2001/XMLSchema#string>.
@@ -39,11 +44,14 @@
 ```
 
 #### Input
+
 ```turtle
 @prefix : <http://example.com/>.
 :a :b ( "apple" "banana" ) .
 ```
+
 #### Output
+
 ```turtle
 <http://example.org/.well-known/genid#018a16a1-9f82-4acd-930e-2be1ea090e83> <http://www.w3.org/1999/02/22-rdf-syntax-ns#first> "apple"^^<http://www.w3.org/2001/XMLSchema#string>.
 <http://example.org/.well-known/genid#4ef6beb7-5e21-4d77-9459-2662b6845375> <http://www.w3.org/1999/02/22-rdf-syntax-ns#first> "banana"^^<http://www.w3.org/2001/XMLSchema#string>.

src/turtle/turtle_doc.rs

@@ -170,7 +170,26 @@ impl<'a> TurtleDoc<'a> {
         })?;
         (buf.as_str(), well_known_prefix).try_into()
     }
-
+    pub fn add_prefixes(
+        &mut self,
+        prefixes: BTreeMap<String, String>,
+    ) -> Result<(), TurtleDocError> {
+        let base = self.base.unwrap_or("");
+        let mut prefixes: BTreeMap<Cow<str>, Cow<str>> = prefixes
+            .into_iter()
+            .map(|(k, v)| (Cow::Owned(k), Cow::Owned(v)))
+            .collect();
+        for (_, prefix) in prefixes.iter_mut() {
+            let iri = IRI::try_from(prefix.as_ref()).map_err(|e| TurtleDocError {
+                message: e.to_string(),
+            })?;
+            if iri.is_relative() {
+                *prefix = Cow::Owned(format!("{base}{prefix}"));
+            }
+        }
+        self.prefixes.extend(prefixes);
+        Ok(())
+    }
     pub fn add_statement(&mut self, subject: Node<'a>, predicate: Node<'a>, object: Node<'a>) {
         let stmt = Statement {
             subject,