--- /dev/null
+from itertools import product
+from pathlib import Path
+from typing import List, Tuple
+
+import black
+from jinja2 import Template
+from pydantic import BaseModel
+
+template_path = Path(__file__).parent.parent / "sqlmodel/sql/expression.py.jinja2"
+destiny_path = Path(__file__).parent.parent / "sqlmodel/sql/expression.py"
+
+
+number_of_types = 4
+
+
+class Arg(BaseModel):
+ name: str
+ annotation: str
+
+
+arg_groups: List[Arg] = []
+
+signatures: List[Tuple[List[Arg], List[str]]] = []
+
+for total_args in range(2, number_of_types + 1):
+ arg_types_tuples = product(["scalar", "model"], repeat=total_args)
+ for arg_type_tuple in arg_types_tuples:
+ args: List[Arg] = []
+ return_types: List[str] = []
+ for i, arg_type in enumerate(arg_type_tuple):
+ if arg_type == "scalar":
+ t_var = f"_TScalar_{i}"
+ arg = Arg(name=f"entity_{i}", annotation=t_var)
+ ret_type = t_var
+ else:
+ t_type = f"_TModel_{i}"
+ t_var = f"Type[{t_type}]"
+ arg = Arg(name=f"entity_{i}", annotation=t_var)
+ ret_type = t_type
+ args.append(arg)
+ return_types.append(ret_type)
+ signatures.append((args, return_types))
+
+template: Template = Template(template_path.read_text())
+
+result = template.render(number_of_types=number_of_types, signatures=signatures)
+
+result = (
+ "# WARNING: do not modify this code, it is generated by "
+ "expression.py.jinja2\n\n" + result
+)
+
+result = black.format_str(result, mode=black.Mode())
+
+destiny_path.write_text(result)