I'm going to need vectors for my target use case.

2 files changed, 43 insertions, 0 deletions

diff --git a/actinide/types.py b/actinide/types.py
index be58b0c..fd86757 100644
--- a/actinide/types.py
+++ b/actinide/types.py
@@ -227,6 +227,45 @@ def flatten(list):
         list = tail(list)
     return r
 
+# ### Vectors
+
+@An.fn
+def vector(*elems):
+    return b.list(elems)
+
+@An.fn
+def vector_p(value):
+    return isinstance(value, b.list)
+
+@An.fn
+def vector_to_list(value):
+    return list(*value)
+
+@An.fn
+def list_to_vector(value):
+    return flatten(list)
+
+@An.fn
+def vector_length(value):
+    return b.len(value)
+
+@An.fn
+def vector_get(value, index):
+    return value[index]
+
+@An.fn
+def vector_set(value, index, elem):
+    value[index] = elem
+    return value
+
+@An.fn
+def vector_add(value, *elems):
+    value.extend(elems)
+    return value
+
+def display_vector(value, symbols):
+    return f"<vector: [{' '.join(display(elem, symbols) for elem in value)}]>"
+
 # ### Procedures
 
 class ProcedureError(Exception):
@@ -306,6 +345,8 @@ def display(value, symbols):
         return display_decimal(value)
     if procedure_p(value):
         return display_procedure(value, symbols)
+    if vector_p(value):
+        return display_vector(value, symbols)
     # Give up and use repr to avoid printing `None`.
     return repr(value)
 
diff --git a/docs/security.rst b/docs/security.rst
index 4a42a2d..027b0de 100644
--- a/docs/security.rst
+++ b/docs/security.rst
@@ -50,6 +50,8 @@ possible:
 
 * Python ``bool`` objects, used to represent Actinide booleans.
 
+* Python ``list`` objects, used to represent Actinide vectors.
+
 * The Python ``None`` constant, used to represent the empty list.
 
 The remaining built-in types are represented using classes: