Create singular polymatrix.from_name to remove ambiguous return type

2 files changed, 8 insertions, 9 deletions

diff --git a/polymatrix/__init__.py b/polymatrix/__init__.py
index a808d92..f68f364 100644
--- a/polymatrix/__init__.py
+++ b/polymatrix/__init__.py
@@ -3,7 +3,7 @@ from polymatrix.expressionstate.init import (
     init_expression_state as internal_init_expression_state,
 )
 from polymatrix.expression.expression import Expression as internal_Expression
-from polymatrix.expression.from_ import from_ as internal_from, from_names as internal_from_names
+from polymatrix.expression.from_ import from_ as internal_from, from_names as internal_from_names, from_name as internal_from_name
 from polymatrix.expression import v_stack as internal_v_stack
 from polymatrix.expression import h_stack as internal_h_stack
 from polymatrix.expression import product as internal_product
@@ -30,3 +30,4 @@ to_matrix_repr = from_polymatrix
 to_dense = from_polymatrix
 to_affine = to_affine_expression
 from_names = internal_from_names
+from_name = internal_from_name
diff --git a/polymatrix/expression/from_.py b/polymatrix/expression/from_.py
index a1303a3..1e50c40 100644
--- a/polymatrix/expression/from_.py
+++ b/polymatrix/expression/from_.py
@@ -33,14 +33,12 @@ def from_(
     )
 
 
-def from_names(names: str, shape: tuple[int, int] = (1,1)) -> tuple[VariableExpression] | VariableExpression:
+def from_names(names: str, shape: tuple[int, int] = (1,1)) -> Iterable[VariableExpression]:
     """ Construct one or multiple variables from comma separated a list of names. """
-    variables = tuple(init_variable_expression(
-                        underlying=polymatrix.expression.init.init_variable_expr(name.strip(), shape))
-                            for name in names.split(","))
+    for name in names.split(","):
+        yield from_name(name.strip(), shape)
 
-    if len(variables) == 1:
-        return variables[0]
-
-    return variables
 
+def from_name(name: str, shape: tuple[int, int] = (1,1)) -> VariableExpression:
+    """ Construct a variable from its names """
+    return init_variable_expression(polymatrix.expression.init.init_variable_expr(name, shape))