[pypy-commit] lang-scheme default: Implementation of Vectors #(...)

[boemmels]

Author: Juergen Boemmels <boemmels at web.de>
Branch: 
Changeset: r17:96e5eb8b8fab
Date: 2011-11-27 17:00 +0100
http://bitbucket.org/pypy/lang-scheme/changeset/96e5eb8b8fab/

Log:	Implementation of Vectors #(...)

diff --git a/scheme/object.py b/scheme/object.py
--- a/scheme/object.py
+++ b/scheme/object.py
@@ -343,6 +343,39 @@
                 self.car.equal(w_obj.car) and \
                 self.cdr.equal(w_obj.cdr)
 
+class W_Vector(W_Root):
+    def __init__(self, vect):
+        self.vect = vect
+
+    def to_repr(self):
+        #strs = map(lambda item: item.to_repr(), self.vect)
+        strs = []
+        for w_item in self.vect:
+            strs.append(w_item.to_repr())
+        return "#(" + " ".join(strs) + ")"
+
+    def to_string(self):
+        #strs = map(lambda item: item.to_string(), self.vect)
+        strs = []
+        for w_item in self.vect:
+            strs.append(w_item.to_string())
+        return "#(" + " ".join(strs) + ")"
+
+    def __repr__(self):
+        return "<W_Vector [" + " ".join(self.vect) + "]>"
+
+    def eval_tr(self, ctx):
+        # vectors can not be evaluated
+        raise SchemeSyntaxError
+
+    def get_len(self):
+        return len(self.vect)
+
+    def get_item(self, offset):
+        if offset < 0 or offset >= len(self.vect):
+            raise SchemeException
+        return self.vect[offset]
+
 class W_Callable(W_Eval):
     def call_tr(self, ctx, lst):
         #usually tail-recursive call is normal call
diff --git a/scheme/ssparser.py b/scheme/ssparser.py
--- a/scheme/ssparser.py
+++ b/scheme/ssparser.py
@@ -2,7 +2,7 @@
 from pypy.rlib.parsing.makepackrat import BacktrackException, Status
 from scheme.object import W_Pair, W_Integer, W_String, symbol, \
         w_nil, W_Boolean, W_Real, quote, qq, unquote, unquote_splicing, \
-        w_ellipsis, W_Character, SchemeSyntaxError
+        w_ellipsis, W_Character, SchemeSyntaxError, W_Vector
 
 def str_unquote(s):
     str_lst = []
@@ -96,6 +96,7 @@
     
     sexpr:
         list
+      | vector  
       | quote
       | qq
       | unquote_splicing
@@ -116,6 +117,14 @@
         IGNORE*
         return {p};
 
+    vector:
+        '#('
+        IGNORE*
+        v = sexpr*
+        ')'
+        IGNORE*
+        return {W_Vector(v)};
+
     pair:
         car = sexpr
         '.'
diff --git a/scheme/test/test_object.py b/scheme/test/test_object.py
--- a/scheme/test/test_object.py
+++ b/scheme/test/test_object.py
@@ -66,6 +66,17 @@
     assert w_sym.to_string() == "symb"
     assert w_sym.to_boolean() is True
 
+def test_vector():
+    w_vect = W_Vector([W_Integer(1), W_Symbol("symb"), W_Integer(2)])
+    assert w_vect.to_boolean() is True
+    assert w_vect.to_repr() == "#(1 symb 2)"
+    assert w_vect.get_len() == 3
+    w_item = w_vect.get_item(2)
+    assert isinstance(w_item, W_Integer)
+    assert w_item.to_fixnum() == 2
+    with py.test.raises(SchemeException):
+        w_vect.get_item(3)
+
 def test_ctx():
     w_fnum = W_Integer(12)
     w_symb = W_Symbol("symb")
diff --git a/scheme/test/test_parser.py b/scheme/test/test_parser.py
--- a/scheme/test/test_parser.py
+++ b/scheme/test/test_parser.py
@@ -1,7 +1,7 @@
 import py
 from scheme.ssparser import parse
 from scheme.object import W_Boolean, W_Real, W_Integer, W_String
-from scheme.object import W_Pair, W_Nil, W_Symbol, W_Character
+from scheme.object import W_Pair, W_Nil, W_Symbol, W_Character, W_Vector
 from pypy.rlib.parsing.makepackrat import BacktrackException
 
 def parse_sexpr(expr):
@@ -201,3 +201,21 @@
     assert isinstance(w_float, W_Symbol)
     assert unwrap(w_float) == "..."
 
+def test_vector():
+    w_vect = parse_sexpr('#()')
+    assert isinstance(w_vect, W_Vector)
+    assert w_vect.get_len() == 0
+    assert w_vect.to_repr() == '#()'
+
+    w_vect = parse_sexpr('#(1 2 symb "string")')
+    assert isinstance(w_vect, W_Vector)
+    assert w_vect.get_len() == 4
+    assert w_vect.to_repr() == '#(1 2 symb "string")'
+
+    w_item0 = w_vect.get_item(0)
+    assert isinstance(w_item0, W_Integer)
+    assert w_item0.to_fixnum() == 1
+
+    w_item2 = w_vect.get_item(2)
+    assert isinstance(w_item2, W_Symbol)
+    assert w_item2.to_string() == "symb"