Move most of the code into new askama_shared crate

This makes it possible to share code between askama and askama_derive.

9 files changed, 8 insertions, 1291 deletions

diff --git a/askama_derive/Cargo.toml b/askama_derive/Cargo.toml
index 61263be..66610ea 100644
--- a/askama_derive/Cargo.toml
+++ b/askama_derive/Cargo.toml
@@ -13,10 +13,9 @@ proc-macro = true
 
 [features]
 default = []
-iron = []
-rocket = []
+iron = ["askama_shared/iron"]
+rocket = ["askama_shared/rocket"]
 
 [dependencies]
-nom = "3"
-quote = "0.3"
+askama_shared = { version = "0.3.4", path = "../askama_shared" }
 syn = "0.11"
diff --git a/askama_derive/src/generator.rs b/askama_derive/src/generator.rs
deleted file mode 100644
index 82f3994..0000000
--- a/askama_derive/src/generator.rs
+++ /dev/null
@@ -1,715 +0,0 @@
-use parser::{self, Cond, Expr, Node, Target, WS};
-use path;
-
-use quote::{Tokens, ToTokens};
-
-use std::{cmp, hash, str};
-use std::path::Path;
-use std::collections::{HashMap, HashSet};
-
-use syn;
-
-pub fn generate(ast: &syn::DeriveInput, path: &Path, mut nodes: Vec<Node>) -> String {
-    let mut base: Option<Expr> = None;
-    let mut blocks = Vec::new();
-    let mut content = Vec::new();
-    let mut macros = HashMap::new();
-    for n in nodes.drain(..) {
-        match n {
-            Node::Extends(path) => {
-                match base {
-                    Some(_) => panic!("multiple extend blocks found"),
-                    None => { base = Some(path); },
-                }
-            },
-            Node::BlockDef(ws1, name, _, ws2) => {
-                blocks.push(n);
-                content.push(Node::Block(ws1, name, ws2));
-            },
-            Node::Macro(ws1, name, params, contents, ws2) => {
-                macros.insert(name, (ws1, name, params, contents, ws2));
-            },
-            _ => { content.push(n); },
-        }
-    }
-
-    let mut gen = Generator::default(&macros);
-    if !blocks.is_empty() {
-        let trait_name = trait_name_for_path(&base, path);
-        if base.is_none() {
-            gen.define_trait(&trait_name, &blocks);
-        } else {
-            let parent_type = get_parent_type(ast)
-                .expect("expected field '_parent' in extending template struct");
-            gen.deref_to_parent(ast, &parent_type);
-        }
-
-        let trait_nodes = if base.is_none() { Some(&content[..]) } else { None };
-        gen.impl_trait(ast, &trait_name, &blocks, trait_nodes);
-        gen.impl_template_for_trait(ast, base.is_some());
-    } else {
-        gen.impl_template(ast, &content);
-    }
-    gen.impl_display(ast);
-    if cfg!(feature = "iron") {
-        gen.impl_modifier_response(ast);
-    }
-    if cfg!(feature = "rocket") {
-        gen.impl_responder(ast, path);
-    }
-    gen.result()
-}
-
-fn trait_name_for_path(base: &Option<Expr>, path: &Path) -> String {
-    let rooted_path = match *base {
-        Some(Expr::StrLit(user_path)) => {
-            path::find_template_from_path(user_path, Some(path))
-        },
-        _ => path.to_path_buf(),
-    };
-
-    let mut res = String::new();
-    res.push_str("TraitFrom");
-    for c in rooted_path.to_string_lossy().chars() {
-        if c.is_alphanumeric() {
-            res.push(c);
-        } else {
-            res.push_str(&format!("{:x}", c as u32));
-        }
-    }
-    res
-}
-
-fn get_parent_type(ast: &syn::DeriveInput) -> Option<&syn::Ty> {
-    match ast.body {
-        syn::Body::Struct(ref data) => {
-            data.fields().iter().filter_map(|f| {
-                f.ident.as_ref().and_then(|name| {
-                    if name.as_ref() == "_parent" {
-                        Some(&f.ty)
-                    } else {
-                        None
-                    }
-                })
-            })
-        },
-        _ => panic!("derive(Template) only works for struct items"),
-    }.next()
-}
-
-struct Generator<'a> {
-    buf: String,
-    indent: u8,
-    start: bool,
-    locals: SetChain<'a, &'a str>,
-    next_ws: Option<&'a str>,
-    skip_ws: bool,
-    macros: &'a MacroMap<'a>,
-}
-
-impl<'a> Generator<'a> {
-
-    fn new<'n>(macros: &'n MacroMap, locals: SetChain<'n, &'n str>, indent: u8) -> Generator<'n> {
-        Generator {
-            buf: String::new(),
-            indent: indent,
-            start: true,
-            locals: locals,
-            next_ws: None,
-            skip_ws: false,
-            macros: macros,
-        }
-    }
-
-    fn default<'n>(macros: &'n MacroMap) -> Generator<'n> {
-        Self::new(macros, SetChain::new(), 0)
-    }
-
-    fn child<'n>(&'n mut self) -> Generator<'n> {
-        let locals = SetChain::with_parent(&self.locals);
-        Self::new(self.macros, locals, self.indent)
-    }
-
-    /* Helper methods for writing to internal buffer */
-
-    fn indent(&mut self) {
-        self.indent += 1;
-    }
-
-    fn dedent(&mut self) {
-        self.indent -= 1;
-    }
-
-    fn write(&mut self, s: &str) {
-        if self.start {
-            for _ in 0..(self.indent * 4) {
-                self.buf.push(' ');
-            }
-            self.start = false;
-        }
-        self.buf.push_str(s);
-    }
-
-    fn writeln(&mut self, s: &str) {
-        if s.is_empty() {
-            return;
-        }
-        if s == "}" {
-            self.dedent();
-        }
-        self.write(s);
-        if s.ends_with('{') {
-            self.indent();
-        }
-        self.buf.push('\n');
-        self.start = true;
-    }
-
-    /* Helper methods for dealing with whitespace nodes */
-
-    fn flush_ws(&mut self, ws: &WS) {
-        if self.next_ws.is_some() && !ws.0 {
-            let val = self.next_ws.unwrap();
-            if !val.is_empty() {
-                self.writeln(&format!("writer.write_str({:#?})?;",
-                                      val));
-            }
-        }
-        self.next_ws = None;
-    }
-
-    fn prepare_ws(&mut self, ws: &WS) {
-        self.skip_ws = ws.1;
-    }
-
-    fn handle_ws(&mut self, ws: &WS) {
-        self.flush_ws(ws);
-        self.prepare_ws(ws);
-    }
-
-    /* Visitor methods for expression types */
-
-    fn visit_num_lit(&mut self, s: &str) {
-        self.write(s);
-    }
-
-    fn visit_str_lit(&mut self, s: &str) {
-        self.write(&format!("\"{}\"", s));
-    }
-
-    fn visit_var(&mut self, s: &str) {
-        if self.locals.contains(s) {
-            self.write(s);
-        } else {
-            self.write(&format!("self.{}", s));
-        }
-    }
-
-    fn visit_attr(&mut self, obj: &Expr, attr: &str) {
-        if let Expr::Var(name) = *obj {
-            if name == "loop" {
-                self.write("_loop_index");
-                if attr == "index" {
-                    self.write(" + 1");
-                    return;
-                } else if attr == "index0" {
-                    return;
-                } else {
-                    panic!("unknown loop variable");
-                }
-            }
-        }
-        self.visit_expr(obj);
-        self.write(&format!(".{}", attr));
-    }
-
-    fn visit_filter(&mut self, name: &str, args: &[Expr]) {
-        if name == "format" {
-            self.write("format!(");
-        } else if BUILT_IN_FILTERS.contains(&name) {
-            self.write(&format!("::askama::filters::{}(&", name));
-        } else {
-            self.write(&format!("filters::{}(&", name));
-        }
-
-        for (i, arg) in args.iter().enumerate() {
-            if i > 0 {
-                self.write(", &");
-            }
-            self.visit_expr(arg);
-        }
-        self.write(")");
-        if name != "format" {
-            self.write("?");
-        }
-    }
-
-    fn visit_binop(&mut self, op: &str, left: &Expr, right: &Expr) {
-        self.visit_expr(left);
-        self.write(&format!(" {} ", op));
-        self.visit_expr(right);
-    }
-
-    fn visit_group(&mut self, inner: &Expr) {
-        self.write("(");
-        self.visit_expr(inner);
-        self.write(")");
-    }
-
-    fn visit_method_call(&mut self, obj: &Expr, method: &str, args: &[Expr]) {
-        self.visit_expr(obj);
-        self.write(&format!(".{}(", method));
-        for (i, arg) in args.iter().enumerate() {
-            if i > 0 {
-                self.write(", ");
-            }
-            self.visit_expr(arg);
-        }
-        self.write(")");
-    }
-
-    fn visit_expr(&mut self, expr: &Expr) {
-        match *expr {
-            Expr::NumLit(s) => self.visit_num_lit(s),
-            Expr::StrLit(s) => self.visit_str_lit(s),
-            Expr::Var(s) => self.visit_var(s),
-            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) =>
-                self.visit_binop(op, left, right),
-            Expr::Group(ref inner) => self.visit_group(inner),
-            Expr::MethodCall(ref obj, method, ref args) =>
-                self.visit_method_call(obj, method, args),
-        }
-    }
-
-    fn visit_target_single<'t>(&mut self, name: &'t str) -> Vec<&'t str> {
-        vec![name]
-    }
-
-    fn visit_target<'t>(&mut self, target: &'t Target) -> Vec<&'t str> {
-        match *target {
-            Target::Name(s) => { self.visit_target_single(s) },
-        }
-    }
-
-    /* Helper methods for handling node types */
-
-    fn write_lit(&mut self, lws: &'a str, val: &str, rws: &'a str) {
-        assert!(self.next_ws.is_none());
-        if !lws.is_empty() {
-            if self.skip_ws {
-                self.skip_ws = false;
-            } else if val.is_empty() {
-                assert!(rws.is_empty());
-                self.next_ws = Some(lws);
-            } else {
-                self.writeln(&format!("writer.write_str({:#?})?;",
-                                      lws));
-            }
-        }
-        if !val.is_empty() {
-            self.writeln(&format!("writer.write_str({:#?})?;", val));
-        }
-        if !rws.is_empty() {
-            self.next_ws = Some(rws);
-        }
-    }
-
-    fn write_expr(&mut self, ws: &WS, s: &Expr) {
-        self.handle_ws(ws);
-        self.write("writer.write_fmt(format_args!(\"{}\", ");
-        self.visit_expr(s);
-        self.writeln("))?;");
-    }
-
-    fn write_call(&mut self, ws: &WS, name: &str, args: &[Expr]) {
-        self.handle_ws(ws);
-        let def = self.macros.get(name).expect(&format!("macro '{}' not found", name));
-        self.locals.push();
-        self.writeln("{");
-        self.prepare_ws(&def.0);
-        for (i, arg) in def.2.iter().enumerate() {
-            self.write(&format!("let {} = &", arg));
-            self.locals.insert(arg);
-            self.visit_expr(&args.get(i)
-                .expect(&format!("macro '{}' takes more than {} arguments", name, i)));
-            self.writeln(";");
-        }
-        self.handle(&def.3);
-        self.flush_ws(&def.4);
-        self.writeln("}");
-        self.locals.pop();
-    }
-
-    fn write_let_decl(&mut self, ws: &WS, var: &'a Target) {
-        self.handle_ws(ws);
-        self.write("let ");
-        match *var {
-            Target::Name(name) => {
-                self.locals.insert(name);
-                self.write(name);
-            },
-        }
-        self.writeln(";");
-    }
-
-    fn write_let(&mut self, ws: &WS, var: &'a Target, val: &Expr) {
-        self.handle_ws(ws);
-        match *var {
-            Target::Name(name) => {
-                if !self.locals.contains(name) {
-                    self.write("let ");
-                    self.locals.insert(name);
-                }
-                self.write(name);
-            },
-        }
-        self.write(" = ");
-        self.visit_expr(val);
-        self.writeln(";");
-    }
-
-    fn write_cond(&mut self, conds: &'a [Cond], ws: &WS) {
-        for (i, &(ref cws, ref cond, ref nodes)) in conds.iter().enumerate() {
-            self.handle_ws(cws);
-            match *cond {
-                Some(ref expr) => {
-                    if i == 0 {
-                        self.write("if ");
-                    } else {
-                        self.dedent();
-                        self.write("} else if ");
-                    }
-                    self.visit_expr(expr);
-                },
-                None => {
-                    self.dedent();
-                    self.write("} else");
-                },
-            }
-            self.writeln(" {");
-            self.locals.push();
-            self.handle(nodes);
-            self.locals.pop();
-        }
-        self.handle_ws(ws);
-        self.writeln("}");
-    }
-
-    fn write_loop(&mut self, ws1: &WS, var: &'a Target, iter: &Expr,
-                  body: &'a [Node], ws2: &WS) {
-        self.handle_ws(ws1);
-        self.locals.push();
-        self.write("for (_loop_index, ");
-        let targets = self.visit_target(var);
-        for name in &targets {
-            self.locals.insert(name);
-            self.write(name);
-        }
-        self.write(") in (&");
-        self.visit_expr(iter);
-        self.writeln(").into_iter().enumerate() {");
-
-        self.handle(body);
-        self.handle_ws(ws2);
-        self.writeln("}");
-        self.locals.pop();
-    }
-
-    fn write_block(&mut self, ws1: &WS, name: &str, ws2: &WS) {
-        self.flush_ws(ws1);
-        self.writeln(&format!("timpl.render_block_{}_into(writer)?;", name));
-        self.prepare_ws(ws2);
-    }
-
-    fn write_block_def(&mut self, ws1: &WS, name: &str, nodes: &'a [Node],
-                       ws2: &WS) {
-        self.writeln("#[allow(unused_variables)]");
-        self.writeln(&format!(
-            "fn render_block_{}_into(&self, writer: &mut ::std::fmt::Write) \
-             -> ::askama::Result<()> {{",
-            name));
-        self.prepare_ws(ws1);
-
-        self.locals.push();
-        self.handle(nodes);
-        self.locals.pop();
-
-        self.flush_ws(ws2);
-        self.writeln("Ok(())");
-        self.writeln("}");
-    }
-
-    fn handle_include(&mut self, ws: &WS, path: &str) {
-        self.prepare_ws(ws);
-        let path = path::find_template_from_path(&path, None);
-        let src = path::get_template_source(&path);
-        let nodes = parser::parse(&src);
-        let nested = {
-            let mut gen = self.child();
-            gen.handle(&nodes);
-            gen.result()
-        };
-        self.buf.push_str(&nested);
-        self.flush_ws(ws);
-    }
-
-    fn handle(&mut self, nodes: &'a [Node]) {
-        for n in nodes {
-            match *n {
-                Node::Lit(lws, val, rws) => { self.write_lit(lws, val, rws); }
-                Node::Comment() => {},
-                Node::Expr(ref ws, ref val) => { self.write_expr(ws, val); },
-                Node::LetDecl(ref ws, ref var) => { self.write_let_decl(ws, var); },
-                Node::Let(ref ws, ref var, ref val) => { self.write_let(ws, var, val); },
-                Node::Cond(ref conds, ref ws) => {
-                    self.write_cond(conds, ws);
-                },
-                Node::Loop(ref ws1, ref var, ref iter, ref body, ref ws2) => {
-                    self.write_loop(ws1, var, iter, body, ws2);
-                },
-                Node::Block(ref ws1, name, ref ws2) => {
-                    self.write_block(ws1, name, ws2);
-                },
-                Node::BlockDef(ref ws1, name, ref block_nodes, ref ws2) => {
-                    self.write_block_def(ws1, name, block_nodes, ws2);
-                }
-                Node::Include(ref ws, ref path) => {
-                    self.handle_include(ws, path);
-                },
-                Node::Call(ref ws, name, ref args) => self.write_call(ws, name, args),
-                Node::Macro(_, _, _, _, _) |
-                Node::Extends(_) => {
-                    panic!("no extends or macros allowed in content");
-                },
-            }
-        }
-    }
-
-    // Writes header for the `impl` for `TraitFromPathName` or `Template`
-    // for the given context struct.
-    fn write_header(&mut self, ast: &syn::DeriveInput, target: &str, extra_anno: &[&str]) {
-        let mut full_anno = Tokens::new();
-        let mut orig_anno = Tokens::new();
-        let need_anno = ast.generics.lifetimes.len() > 0 ||
-                        ast.generics.ty_params.len() > 0 ||
-                        extra_anno.len() > 0;
-        if need_anno {
-            full_anno.append("<");
-            orig_anno.append("<");
-        }
-
-        let (mut full_sep, mut orig_sep) = (false, false);
-        for lt in &ast.generics.lifetimes {
-            if full_sep {
-                full_anno.append(",");
-            }
-            if orig_sep {
-                orig_anno.append(",");
-            }
-            lt.to_tokens(&mut full_anno);
-            lt.to_tokens(&mut orig_anno);
-            full_sep = true;
-            orig_sep = true;
-        }
-
-        for anno in extra_anno {
-            if full_sep {
-                full_anno.append(",");
-            }
-            full_anno.append(anno);
-            full_sep = true;
-        }
-
-        for param in &ast.generics.ty_params {
-            if full_sep {
-                full_anno.append(",");
-            }
-            if orig_sep {
-                orig_anno.append(",");
-            }
-            let mut impl_param = param.clone();
-            impl_param.default = None;
-            impl_param.to_tokens(&mut full_anno);
-            param.ident.to_tokens(&mut orig_anno);
-            full_sep = true;
-            orig_sep = true;
-        }
-
-        if need_anno {
-            full_anno.append(">");
-            orig_anno.append(">");
-        }
-
-        let mut where_clause = Tokens::new();
-        ast.generics.where_clause.to_tokens(&mut where_clause);
-        self.writeln(&format!("impl{} {} for {}{}{} {{",
-                              full_anno.as_str(), target, ast.ident.as_ref(),
-                              orig_anno.as_str(), where_clause.as_str()));
-    }
-
-    // Implement `Template` for the given context struct.
-    fn impl_template(&mut self, ast: &syn::DeriveInput, nodes: &'a [Node]) {
-        self.write_header(ast, "::askama::Template", &vec![]);
-        self.writeln("fn render_into(&self, writer: &mut ::std::fmt::Write) -> \
-                      ::askama::Result<()> {");
-        self.handle(nodes);
-        self.flush_ws(&WS(false, false));
-        self.writeln("Ok(())");
-        self.writeln("}");
-        self.writeln("}");
-    }
-
-    // Implement `Display` for the given context struct.
-    fn impl_display(&mut self, ast: &syn::DeriveInput) {
-        self.write_header(ast, "::std::fmt::Display", &vec![]);
-        self.writeln("fn fmt(&self, f: &mut ::std::fmt::Formatter) -> ::std::fmt::Result {");
-        self.writeln("self.render_into(f).map_err(|_| ::std::fmt::Error {})");
-        self.writeln("}");
-        self.writeln("}");
-    }
-
-    // Implement `Deref<Parent>` for an inheriting context struct.
-    fn deref_to_parent(&mut self, ast: &syn::DeriveInput, parent_type: &syn::Ty) {
-        self.write_header(ast, "::std::ops::Deref", &vec![]);
-        let mut tokens = Tokens::new();
-        parent_type.to_tokens(&mut tokens);
-        self.writeln(&format!("type Target = {};", tokens.as_str()));
-        self.writeln("fn deref(&self) -> &Self::Target {");
-        self.writeln("&self._parent");
-        self.writeln("}");
-        self.writeln("}");
-    }
-
-    // Implement `TraitFromPathName` for the given context struct.
-    fn impl_trait(&mut self, ast: &syn::DeriveInput, trait_name: &str,
-                  blocks: &'a [Node], nodes: Option<&'a [Node]>) {
-        self.write_header(ast, &trait_name, &vec![]);
-        self.handle(blocks);
-
-        self.writeln("#[allow(unused_variables)]");
-        self.writeln(&format!(
-            "fn render_trait_into(&self, timpl: &{}, writer: &mut ::std::fmt::Write) \
-             -> ::askama::Result<()> {{",
-            trait_name));
-
-        if let Some(nodes) = nodes {
-            self.handle(nodes);
-            self.flush_ws(&WS(false, false));
-        } else {
-            self.writeln("self._parent.render_trait_into(self, writer)?;");
-        }
-
-        self.writeln("Ok(())");
-        self.writeln("}");
-        self.flush_ws(&WS(false, false));
-        self.writeln("}");
-    }
-
-    // Implement `Template` for templates that implement a template trait.
-    fn impl_template_for_trait(&mut self, ast: &syn::DeriveInput, derived: bool) {
-        self.write_header(ast, "::askama::Template", &vec![]);
-        self.writeln("fn render_into(&self, writer: &mut ::std::fmt::Write) \
-                      -> ::askama::Result<()> {");
-        if derived {
-            self.writeln("self._parent.render_trait_into(self, writer)?;");
-        } else {
-            self.writeln("self.render_trait_into(self, writer)?;");
-        }
-        self.writeln("Ok(())");
-        self.writeln("}");
-        self.writeln("}");
-    }
-
-    // Defines the `TraitFromPathName` trait.
-    fn define_trait(&mut self, trait_name: &str, blocks: &'a [Node]) {
-        self.writeln(&format!("trait {} {{", &trait_name));
-        self.handle(blocks);
-        self.writeln(&format!(
-            "fn render_trait_into(&self, timpl: &{}, writer: &mut ::std::fmt::Write) \
-             -> ::askama::Result<()>;",
-            trait_name));
-        self.writeln("}");
-    }
-
-    // Implement iron's Modifier<Response> if enabled
-    fn impl_modifier_response(&mut self, ast: &syn::DeriveInput) {
-        self.write_header(ast, "::askama::iron::Modifier<::askama::iron::Response>", &vec![]);
-        self.writeln("fn modify(self, res: &mut ::askama::iron::Response) {");
-        self.writeln("res.body = Some(Box::new(self.render().unwrap().into_bytes()));");
-        self.writeln("}");
-        self.writeln("}");
-    }
-
-    // Implement Rocket's `Responder`.
-    fn impl_responder(&mut self, ast: &syn::DeriveInput, path: &Path) {
-        self.write_header(ast, "::askama::rocket::Responder<'r>", &vec!["'r"]);
-        self.writeln("fn respond_to(self, _: &::askama::rocket::Request) \
-                      -> ::std::result::Result<\
-                         ::askama::rocket::Response<'r>, ::askama::rocket::Status> {");
-        let ext = match path.extension() {
-            Some(s) => s.to_str().unwrap(),
-            None => "txt",
-        };
-        self.writeln("::askama::rocket::Response::build()");
-        self.indent();
-        self.writeln(&format!(".header(::askama::rocket::ContentType::from_extension({:?})\
-                               .unwrap())", ext));
-        self.writeln(".sized_body(::std::io::Cursor::new(self.render().unwrap()))");
-        self.writeln(".ok()");
-        self.dedent();
-        self.writeln("}");
-        self.writeln("}");
-    }
-
-    fn result(self) -> String {
-        self.buf
-    }
-
-}
-
-struct SetChain<'a, T: 'a> where T: cmp::Eq + hash::Hash {
-    parent: Option<&'a SetChain<'a, T>>,
-    scopes: Vec<HashSet<T>>,
-}
-
-impl<'a, T: 'a> SetChain<'a, T> where T: cmp::Eq + hash::Hash {
-    fn new() -> SetChain<'a, T> {
-        SetChain { parent: None, scopes: vec![HashSet::new()] }
-    }
-    fn with_parent<'p>(parent: &'p SetChain<T>) -> SetChain<'p, T> {
-        SetChain { parent: Some(parent), scopes: vec![HashSet::new()] }
-    }
-    fn contains(&self, val: T) -> bool {
-        self.scopes.iter().rev().any(|set| set.contains(&val)) ||
-            match self.parent {
-                Some(set) => set.contains(val),
-                None => false,
-            }
-    }
-    fn insert(&mut self, val: T) {
-        self.scopes.last_mut().unwrap().insert(val);
-    }
-    fn push(&mut self) {
-        self.scopes.push(HashSet::new());
-    }
-    fn pop(&mut self) {
-        self.scopes.pop().unwrap();
-        assert!(self.scopes.len() > 0);
-    }
-}
-
-type MacroMap<'a> = HashMap<&'a str, (WS, &'a str, Vec<&'a str>, Vec<Node<'a>>, WS)>;
-
-const BUILT_IN_FILTERS: [&str; 9] = [
-    "e",
-    "escape",
-    "format",
-    "lower",
-    "lowercase",
-    "trim",
-    "upper",
-    "uppercase",
-    "json", // Optional feature; reserve the name anyway
-];
diff --git a/askama_derive/src/lib.rs b/askama_derive/src/lib.rs
index 0564ccc..0333c06 100644
--- a/askama_derive/src/lib.rs
+++ b/askama_derive/src/lib.rs
@@ -1,7 +1,5 @@
-#[macro_use]
-extern crate nom;
+extern crate askama_shared as shared;
 extern crate proc_macro;
-extern crate quote;
 extern crate syn;
 
 use proc_macro::TokenStream;
@@ -9,10 +7,6 @@ use proc_macro::TokenStream;
 use std::borrow::Cow;
 use std::path::PathBuf;
 
-mod generator;
-mod parser;
-mod path;
-
 #[proc_macro_derive(Template, attributes(template))]
 pub fn derive_template(input: TokenStream) -> TokenStream {
     let ast = syn::parse_derive_input(&input.to_string()).unwrap();
@@ -35,16 +29,16 @@ fn build_template(ast: &syn::DeriveInput) -> String {
     let (path, src) = match meta.source {
         Source::Source(s) => (PathBuf::new(), Cow::Borrowed(s)),
         Source::Path(s) => {
-            let path = path::find_template_from_path(&s, None);
-            let src = path::get_template_source(&path);
+            let path = shared::path::find_template_from_path(&s, None);
+            let src = shared::path::get_template_source(&path);
             (path, Cow::Owned(src))
         },
     };
-    let nodes = parser::parse(src.as_ref());
+    let nodes = shared::parse(src.as_ref());
     if meta.print == Print::Ast || meta.print == Print::All {
         println!("{:?}", nodes);
     }
-    let code = generator::generate(ast, &path, nodes);
+    let code = shared::generate(ast, &path, nodes);
     if meta.print == Print::Code || meta.print == Print::All {
         println!("{}", code);
     }
diff --git a/askama_derive/src/parser.rs b/askama_derive/src/parser.rs
deleted file mode 100644
index 8732f0e..0000000
--- a/askama_derive/src/parser.rs
+++ /dev/null
@@ -1,471 +0,0 @@
-use nom::{self, IResult};
-use std::str;
-
-#[derive(Debug)]
-pub enum Expr<'a> {
-    NumLit(&'a str),
-    StrLit(&'a str),
-    Var(&'a str),
-    Attr(Box<Expr<'a>>, &'a str),
-    Filter(&'a str, Vec<Expr<'a>>),
-    BinOp(&'a str, Box<Expr<'a>>, Box<Expr<'a>>),
-    Group(Box<Expr<'a>>),
-    MethodCall(Box<Expr<'a>>, &'a str, Vec<Expr<'a>>),
-}
-
-#[derive(Debug)]
-pub enum Target<'a> {
-    Name(&'a str),
-}
-
-#[derive(Clone, Copy, Debug)]
-pub struct WS(pub bool, pub bool);
-
-#[derive(Debug)]
-pub enum Node<'a> {
-    Lit(&'a str, &'a str, &'a str),
-    Comment(),
-    Expr(WS, Expr<'a>),
-    Call(WS, &'a str, Vec<Expr<'a>>),
-    LetDecl(WS, Target<'a>),
-    Let(WS, Target<'a>, Expr<'a>),
-    Cond(Vec<(WS, Option<Expr<'a>>, Vec<Node<'a>>)>, WS),
-    Loop(WS, Target<'a>, Expr<'a>, Vec<Node<'a>>, WS),
-    Extends(Expr<'a>),
-    BlockDef(WS, &'a str, Vec<Node<'a>>, WS),
-    Block(WS, &'a str, WS),
-    Include(WS, &'a str),
-    Macro(WS, &'a str, Vec<&'a str>, Vec<Node<'a>>, WS),
-}
-
-pub type Cond<'a> = (WS, Option<Expr<'a>>, Vec<Node<'a>>);
-
-fn split_ws_parts(s: &[u8]) -> Node {
-    if s.is_empty() {
-        let rs = str::from_utf8(s).unwrap();
-        return Node::Lit(rs, rs, rs);
-    }
-    let is_ws = |c: &u8| {
-        *c != b' ' && *c != b'\t' && *c != b'\r' && *c != b'\n'
-    };
-    let start = s.iter().position(&is_ws);
-    let res = if start.is_none() {
-            (s, &s[0..0], &s[0..0])
-        } else {
-            let start = start.unwrap();
-            let end = s.iter().rposition(&is_ws);
-            if end.is_none() {
-                (&s[..start], &s[start..], &s[0..0])
-            } else {
-                let end = end.unwrap();
-                (&s[..start], &s[start..end + 1], &s[end + 1..])
-            }
-        };
-    Node::Lit(str::from_utf8(res.0).unwrap(),
-              str::from_utf8(res.1).unwrap(),
-              str::from_utf8(res.2).unwrap())
-}
-
-enum ContentState {
-    Any,
-    Brace(usize),
-    End(usize),
-}
-
-fn take_content(i: &[u8]) -> IResult<&[u8], Node> {
-    use parser::ContentState::*;
-    let mut state = Any;
-    for (idx, c) in i.iter().enumerate() {
-        state = match (state, *c) {
-            (Any, b'{') => Brace(idx),
-            (Any, _) => Any,
-            (Brace(start), b'{') |
-            (Brace(start), b'%') |
-            (Brace(start), b'#') => End(start),
-            (Brace(_), _) => Any,
-            (End(_), _) => panic!("cannot happen"),
-        };
-        if let End(_) = state {
-            break;
-        }
-    }
-    match state {
-        Any |
-        Brace(_) => IResult::Done(&i[..0], split_ws_parts(i)),
-        End(0) => IResult::Error(nom::ErrorKind::Custom(0)),
-        End(start) => IResult::Done(&i[start..], split_ws_parts(&i[..start])),
-    }
-}
-
-fn identifier(input: &[u8]) -> IResult<&[u8], &str> {
-    if !nom::is_alphabetic(input[0]) && input[0] != b'_' {
-        return IResult::Error(nom::ErrorKind::Custom(0));
-    }
-    for (i, ch) in input.iter().enumerate() {
-        if i == 0 || nom::is_alphanumeric(*ch) || *ch == b'_' {
-            continue;
-        }
-        return IResult::Done(&input[i..],
-                             str::from_utf8(&input[..i]).unwrap());
-    }
-    IResult::Done(&input[1..], str::from_utf8(&input[..1]).unwrap())
-}
-
-named!(expr_num_lit<Expr>, map!(nom::digit,
-    |s| Expr::NumLit(str::from_utf8(s).unwrap())
-));
-
-named!(expr_str_lit<Expr>, map!(
-    delimited!(char!('"'), is_not!("\""), char!('"')),
-    |s| Expr::StrLit(str::from_utf8(s).unwrap())
-));
-
-named!(expr_var<Expr>, map!(identifier,
-    |s| Expr::Var(s))
-);
-
-named!(target_single<Target>, map!(identifier,
-    |s| Target::Name(s)
-));
-
-named!(arguments<Vec<Expr>>, do_parse!(
-    tag_s!("(") >>
-    args: opt!(do_parse!(
-        arg0: ws!(expr_any) >>
-        args: many0!(do_parse!(
-            tag_s!(",") >>
-            argn: ws!(expr_any) >>
-            (argn)
-        )) >>
-        ({
-           let mut res = vec![arg0];
-           res.extend(args);
-           res
-        })
-    )) >>
-    tag_s!(")") >>
-    (args.unwrap_or(Vec::new()))
-));
-
-named!(parameters<Vec<&'a str>>, do_parse!(
-    tag_s!("(") >>
-    vals: opt!(do_parse!(
-        arg0: ws!(identifier) >>
-        args: many0!(do_parse!(
-            tag_s!(",") >>
-            argn: ws!(identifier) >>
-            (argn)
-        )) >>
-        ({
-            let mut res = vec![arg0];
-            res.extend(args);
-            res
-        })
-    )) >>
-    tag_s!(")") >>
-    (vals.unwrap_or(Vec::new()))
-));
-
-named!(expr_group<Expr>, map!(
-    delimited!(char!('('), expr_any, char!(')')),
-    |s| Expr::Group(Box::new(s))
-));
-
-named!(expr_single<Expr>, alt!(
-    expr_num_lit |
-    expr_str_lit |
-    expr_var |
-    expr_group
-));
-
-named!(attr<(&str, Option<Vec<Expr>>)>, do_parse!(
-    tag_s!(".") >>
-    attr: identifier >>
-    args: opt!(arguments) >>
-    (attr, args)
-));
-
-named!(expr_attr<Expr>, do_parse!(
-    obj: expr_single >>
-    attrs: many0!(attr) >>
-    ({
-        let mut res = obj;
-        for (aname, args) in attrs {
-            res = if args.is_some() {
-                Expr::MethodCall(Box::new(res), aname, args.unwrap())
-            } else {
-                Expr::Attr(Box::new(res), aname)
-            };
-        }
-        res
-    })
-));
-
-named!(filter<(&str, Option<Vec<Expr>>)>, do_parse!(
-    tag_s!("|") >>
-    fname: identifier >>
-    args: opt!(arguments) >>
-    (fname, args)
-));
-
-named!(expr_filtered<Expr>, do_parse!(
-    obj: expr_attr >>
-    filters: many0!(filter) >>
-    ({
-       let mut res = obj;
-       for (fname, args) in filters {
-           res = Expr::Filter(fname, {
-               let mut args = match args {
-                   Some(inner) => inner,
-                   None => Vec::new(),
-               };
-               args.insert(0, res);
-               args
-           });
-       }
-       res
-    })
-));
-
-macro_rules! expr_prec_layer {
-    ( $name:ident, $inner:ident, $( $op:expr ),* ) => {
-        named!($name<Expr>, alt!(
-            do_parse!(
-                left: $inner >>
-                op: ws!(alt!($( tag_s!($op) )|*)) >>
-                right: $inner >>
-                (Expr::BinOp(str::from_utf8(op).unwrap(),
-                             Box::new(left), Box::new(right)))
-            ) | $inner
-        ));
-    }
-}
-
-expr_prec_layer!(expr_muldivmod, expr_filtered, "*", "/", "%");
-expr_prec_layer!(expr_addsub, expr_muldivmod, "+", "-");
-expr_prec_layer!(expr_shifts, expr_addsub, ">>", "<<");
-expr_prec_layer!(expr_band, expr_shifts, "&");
-expr_prec_layer!(expr_bxor, expr_band, "^");
-expr_prec_layer!(expr_bor, expr_bxor, "|");
-expr_prec_layer!(expr_compare, expr_bor,
-    "==", "!=", ">=", ">", "<=", "<"
-);
-expr_prec_layer!(expr_and, expr_compare, "&&");
-expr_prec_layer!(expr_any, expr_and, "||");
-
-named!(expr_node<Node>, do_parse!(
-    tag_s!("{{") >>
-    pws: opt!(tag_s!("-")) >>
-    expr: ws!(expr_any) >>
-    nws: opt!(tag_s!("-")) >>
-    tag_s!("}}") >>
-    (Node::Expr(WS(pws.is_some(), nws.is_some()), expr))
-));
-
-named!(block_call<Node>, do_parse!(
-    pws: opt!(tag_s!("-")) >>
-    ws!(tag_s!("call")) >>
-    name: ws!(identifier) >>
-    args: ws!(arguments) >>
-    nws: opt!(tag_s!("-")) >>
-    (Node::Call(WS(pws.is_some(), nws.is_some()), name, args))
-));
-
-named!(cond_if<Expr>, do_parse!(
-    ws!(tag_s!("if")) >>
-    cond: ws!(expr_any) >>
-    (cond)
-));
-
-named!(cond_block<Cond>, do_parse!(
-    tag_s!("{%") >>
-    pws: opt!(tag_s!("-")) >>
-    ws!(tag_s!("else")) >>
-    cond: opt!(cond_if) >>
-    nws: opt!(tag_s!("-")) >>
-    tag_s!("%}") >>
-    block: parse_template >>
-    (WS(pws.is_some(), nws.is_some()), cond, block)
-));
-
-named!(block_if<Node>, do_parse!(
-    pws1: opt!(tag_s!("-")) >>
-    cond: ws!(cond_if) >>
-    nws1: opt!(tag_s!("-")) >>
-    tag_s!("%}") >>
-    block: parse_template >>
-    elifs: many0!(cond_block) >>
-    tag_s!("{%") >>
-    pws2: opt!(tag_s!("-")) >>
-    ws!(tag_s!("endif")) >>
-    nws2: opt!(tag_s!("-")) >>
-    ({
-       let mut res = Vec::new();
-       res.push((WS(pws1.is_some(), nws1.is_some()), Some(cond), block));
-       res.extend(elifs);
-       Node::Cond(res, WS(pws2.is_some(), nws2.is_some()))
-    })
-));
-
-named!(block_let<Node>, do_parse!(
-    pws: opt!(tag_s!("-")) >>
-    ws!(tag_s!("let")) >>
-    var: ws!(target_single) >>
-    val: opt!(do_parse!(
-        ws!(tag_s!("=")) >>
-        val: ws!(expr_any) >>
-        (val)
-    )) >>
-    nws: opt!(tag_s!("-")) >>
-    (if val.is_some() {
-        Node::Let(WS(pws.is_some(), nws.is_some()), var, val.unwrap())
-    } else {
-        Node::LetDecl(WS(pws.is_some(), nws.is_some()), var)
-    })
-));
-
-named!(block_for<Node>, do_parse!(
-    pws1: opt!(tag_s!("-")) >>
-    ws!(tag_s!("for")) >>
-    var: ws!(target_single) >>
-    ws!(tag_s!("in")) >>
-    iter: ws!(expr_any) >>
-    nws1: opt!(tag_s!("-")) >>
-    tag_s!("%}") >>
-    block: parse_template >>
-    tag_s!("{%") >>
-    pws2: opt!(tag_s!("-")) >>
-    ws!(tag_s!("endfor")) >>
-    nws2: opt!(tag_s!("-")) >>
-    (Node::Loop(WS(pws1.is_some(), nws1.is_some()),
-                var, iter, block,
-                WS(pws2.is_some(), pws2.is_some())))
-));
-
-named!(block_extends<Node>, do_parse!(
-    ws!(tag_s!("extends")) >>
-    name: ws!(expr_str_lit) >>
-    (Node::Extends(name))
-));
-
-named!(block_block<Node>, do_parse!(
-    pws1: opt!(tag_s!("-")) >>
-    ws!(tag_s!("block")) >>
-    name: ws!(identifier) >>
-    nws1: opt!(tag_s!("-")) >>
-    tag_s!("%}") >>
-    contents: parse_template >>
-    tag_s!("{%") >>
-    pws2: opt!(tag_s!("-")) >>
-    ws!(tag_s!("endblock")) >>
-    opt!(ws!(tag_s!(name))) >>
-    nws2: opt!(tag_s!("-")) >>
-    (Node::BlockDef(WS(pws1.is_some(), nws1.is_some()),
-                    name, contents,
-                    WS(pws2.is_some(), pws2.is_some())))
-));
-
-named!(block_include<Node>, do_parse!(
-    pws: opt!(tag_s!("-")) >>
-    ws!(tag_s!("include")) >>
-    name: ws!(expr_str_lit) >>
-    nws: opt!(tag_s!("-")) >>
-    (Node::Include(WS(pws.is_some(), nws.is_some()), match name {
-        Expr::StrLit(s) => s,
-        _ => panic!("include path must be a string literal"),
-    }))
-));
-
-named!(block_macro<Node>, do_parse!(
-    pws1: opt!(tag_s!("-")) >>
-    ws!(tag_s!("macro")) >>
-    name: ws!(identifier) >>
-    params: ws!(parameters) >>
-    nws1: opt!(tag_s!("-")) >>
-    tag_s!("%}") >>
-    contents: parse_template >>
-    tag_s!("{%") >>
-    pws2: opt!(tag_s!("-")) >>
-    ws!(tag_s!("endmacro")) >>
-    nws2: opt!(tag_s!("-")) >>
-    (Node::Macro(
-         WS(pws1.is_some(), nws1.is_some()),
-         name,
-         params,
-         contents,
-         WS(pws2.is_some(), nws2.is_some())
-    ))
-));
-
-named!(block_node<Node>, do_parse!(
-    tag_s!("{%") >>
-    contents: alt!(
-        block_call |
-        block_let |
-        block_if |
-        block_for |
-        block_extends |
-        block_include |
-        block_block |
-        block_macro
-    ) >>
-    tag_s!("%}") >>
-    (contents)
-));
-
-named!(block_comment<Node>, do_parse!(
-    tag_s!("{#") >>
-    take_until_s!("#}") >>
-    tag_s!("#}") >>
-    (Node::Comment())
-));
-
-named!(parse_template<Vec<Node<'a>>>, many0!(alt!(
-    take_content |
-    block_comment |
-    expr_node |
-    block_node
-)));
-
-pub fn parse(src: &str) -> Vec<Node> {
-    match parse_template(src.as_bytes()) {
-        IResult::Done(left, res) => {
-            if left.len() > 0 {
-                let s = str::from_utf8(left).unwrap();
-                panic!("unable to parse template:\n\n{:?}", s);
-            } else {
-                res
-            }
-        },
-        IResult::Error(err) => panic!("problems parsing template source: {}", err),
-        IResult::Incomplete(_) => panic!("parsing incomplete"),
-    }
-}
-
-#[cfg(test)]
-mod tests {
-    fn check_ws_split(s: &str, res: &(&str, &str, &str)) {
-        let node = super::split_ws_parts(s.as_bytes());
-        match node {
-            super::Node::Lit(lws, s, rws) => {
-                assert_eq!(lws, res.0);
-                assert_eq!(s, res.1);
-                assert_eq!(rws, res.2);
-            },
-            _ => { panic!("fail"); },
-        }
-    }
-    #[test]
-    fn test_ws_splitter() {
-        check_ws_split("", &("", "", ""));
-        check_ws_split("a", &("", "a", ""));
-        check_ws_split("\ta", &("\t", "a", ""));
-        check_ws_split("b\n", &("", "b", "\n"));
-        check_ws_split(" \t\r\n", &(" \t\r\n", "", ""));
-    }
-    #[test]
-    #[should_panic]
-    fn test_invalid_block() {
-        super::parse("{% extend \"blah\" %}");
-    }
-}
diff --git a/askama_derive/src/path.rs b/askama_derive/src/path.rs
deleted file mode 100644
index 3c04965..0000000
--- a/askama_derive/src/path.rs
+++ /dev/null
@@ -1,86 +0,0 @@
-use std::env;
-use std::fs::File;
-use std::io::Read;
-use std::path::{Path, PathBuf};
-
-pub fn get_template_source(tpl_path: &Path) -> String {
-    let mut path = template_dir();
-    path.push(tpl_path);
-    let mut f = match File::open(&path) {
-        Err(_) => {
-            let msg = format!("unable to open template file '{}'",
-                              &path.to_str().unwrap());
-            panic!(msg);
-        },
-        Ok(f) => f,
-    };
-    let mut s = String::new();
-    f.read_to_string(&mut s).unwrap();
-    if s.ends_with('\n') {
-        let _ = s.pop();
-    }
-    s
-}
-
-pub fn find_template_from_path<'a>(path: &str, start_at: Option<&Path>) -> PathBuf {
-    let root = template_dir();
-    if let Some(rel) = start_at {
-        let mut fs_rel_path = root.clone();
-        fs_rel_path.push(rel);
-        fs_rel_path = fs_rel_path.with_file_name(path);
-        if fs_rel_path.exists() {
-            return fs_rel_path.strip_prefix(&root).unwrap().to_owned();
-        }
-    }
-
-    let mut fs_abs_path = root.clone();
-    let path = Path::new(path);
-    fs_abs_path.push(Path::new(path));
-    if fs_abs_path.exists() {
-        path.to_owned()
-    } else {
-        panic!(format!("template '{:?}' not found", path.to_str()));
-    }
-}
-
-// Duplicated in askama
-fn template_dir() -> PathBuf {
-    let mut path = PathBuf::from(env::var("CARGO_MANIFEST_DIR").unwrap());
-    path.push("templates");
-    path
-}
-
-#[cfg(test)]
-mod tests {
-    use super::{find_template_from_path, get_template_source};
-    use super::Path;
-
-    #[test]
-    fn get_source() {
-        assert_eq!(get_template_source(Path::new("sub/b.html")), "bar");
-    }
-
-    #[test]
-    fn find_absolute() {
-        let path = find_template_from_path("sub/b.html", Some(Path::new("a.html")));
-        assert_eq!(path, Path::new("sub/b.html"));
-    }
-
-    #[test]
-    #[should_panic]
-    fn find_relative_nonexistent() {
-        find_template_from_path("b.html", Some(Path::new("a.html")));
-    }
-
-    #[test]
-    fn find_relative() {
-        let path = find_template_from_path("c.html", Some(Path::new("sub/b.html")));
-        assert_eq!(path, Path::new("sub/c.html"));
-    }
-
-    #[test]
-    fn find_relative_sub() {
-        let path = find_template_from_path("sub1/d.html", Some(Path::new("sub/b.html")));
-        assert_eq!(path, Path::new("sub/sub1/d.html"));
-    }
-}
diff --git a/askama_derive/templates/a.html b/askama_derive/templates/a.html
deleted file mode 100644
index 257cc56..0000000
--- a/askama_derive/templates/a.html
+++ /dev/null
@@ -1 +0,0 @@
-foo
diff --git a/askama_derive/templates/sub/b.html b/askama_derive/templates/sub/b.html
deleted file mode 100644
index 5716ca5..0000000
--- a/askama_derive/templates/sub/b.html
+++ /dev/null
@@ -1 +0,0 @@
-bar
diff --git a/askama_derive/templates/sub/c.html b/askama_derive/templates/sub/c.html
deleted file mode 100644
index 7601807..0000000
--- a/askama_derive/templates/sub/c.html
+++ /dev/null
@@ -1 +0,0 @@
-baz
diff --git a/askama_derive/templates/sub/sub1/d.html b/askama_derive/templates/sub/sub1/d.html
deleted file mode 100644
index fa11a6a..0000000
--- a/askama_derive/templates/sub/sub1/d.html
+++ /dev/null
@@ -1 +0,0 @@
-echo