Handle path expressions (fixes #56)

2 files changed, 29 insertions, 0 deletions

diff --git a/askama_shared/src/generator.rs b/askama_shared/src/generator.rs
index ab861dc..4588677 100644
--- a/askama_shared/src/generator.rs
+++ b/askama_shared/src/generator.rs
@@ -561,6 +561,7 @@ impl<'a> Generator<'a> {
             Expr::NumLit(s) => self.visit_num_lit(s),
             Expr::StrLit(s) => self.visit_str_lit(s),
             Expr::Var(s) => self.visit_var(s),
+            Expr::Path(ref path) => self.visit_path(path),
             Expr::Attr(ref obj, name) => self.visit_attr(obj, name),
             Expr::Filter(name, ref args) => self.visit_filter(name, args),
             Expr::BinOp(op, ref left, ref right) =>
@@ -671,6 +672,16 @@ impl<'a> Generator<'a> {
         DisplayWrap::Unwrapped
     }
 
+    fn visit_path(&mut self, path: &Vec<&str>) -> DisplayWrap {
+        for (i, part) in path.iter().enumerate() {
+            if i > 0 {
+                self.write("::");
+            }
+            self.write(part);
+        }
+        DisplayWrap::Unwrapped
+    }
+
     fn visit_var(&mut self, s: &str) -> DisplayWrap {
         if self.locals.contains(s) {
             self.write(s);
diff --git a/askama_shared/src/parser.rs b/askama_shared/src/parser.rs
index 083e96b..495b68f 100644
--- a/askama_shared/src/parser.rs
+++ b/askama_shared/src/parser.rs
@@ -6,6 +6,7 @@ pub enum Expr<'a> {
     NumLit(&'a str),
     StrLit(&'a str),
     Var(&'a str),
+    Path(Vec<&'a str>),
     Attr(Box<Expr<'a>>, &'a str),
     Filter(&'a str, Vec<Expr<'a>>),
     BinOp(&'a str, Box<Expr<'a>>, Box<Expr<'a>>),
@@ -136,6 +137,22 @@ named!(expr_var<Expr>, map!(identifier,
     |s| Expr::Var(s))
 );
 
+named!(expr_path<Expr>, do_parse!(
+    start: call!(identifier) >>
+    rest: many1!(do_parse!(
+        tag_s!("::") >>
+        part: identifier >>
+        (part)
+    )) >>
+    ({
+        let mut path = vec![ start ];
+        for part in rest.iter() {
+            path.push(part);
+        }
+        Expr::Path(path)
+    })
+));
+
 named!(target_single<Target>, map!(identifier,
     |s| Target::Name(s)
 ));
@@ -186,6 +203,7 @@ named!(expr_group<Expr>, map!(
 named!(expr_single<Expr>, alt!(
     expr_num_lit |
     expr_str_lit |
+    expr_path |
     expr_var |
     expr_group
 ));