Make CLI print errors

src/tensora/cli.py

@@ -6,6 +6,7 @@
 import typer
 from parsita import Failure, Success
 
+from .desugar.exceptions import DiagonalAccessError, NoKernelFoundError
 from .expression import parse_assignment
 from .format import Format, Mode, parse_format
 from .kernel_type import KernelType
@@ -97,7 +98,11 @@ def tensora(
             formats[variable_name] = Format((Mode.dense,) * order, tuple(range(order)))
 
     # Generate code
-    code = generate_c_code_from_parsed(sugar, formats, kernel_types)
+    try:
+        code = generate_c_code_from_parsed(sugar, formats, kernel_types)
+    except (DiagonalAccessError, NoKernelFoundError) as error:
+        typer.echo(error, err=True)
+        raise typer.Exit(1)
 
     if output_path is None:
         typer.echo(code)

src/tensora/desugar/exceptions.py

@@ -12,14 +12,14 @@ class DiagonalAccessError(Exception):
     def __str__(self) -> str:
         return (
             f"Diagonal access to a tensor (i.e. repeating the same index within a tensor) is not "
-            f"currently supported: {self.tensor.name}({', '.join(self.tensor.indexes)}"
+            f"currently supported: {self.tensor.name}({', '.join(self.tensor.indexes)})"
         )
 
 
 @dataclass(frozen=True, slots=True)
 class NoKernelFoundError(Exception):
     def __str__(self) -> str:
         return (
-            "Was unable to find a kernel to solve the given tensor expression. This is likely "
-            "due to sparse tensors needing to be iterated in opposite orders."
+            "Tensora's tensor algebra compiler was unable to find a kernel for the given problem. "
+            "This is likely due to sparse tensors needing to be iterated in opposite orders."
         )