Initial Checks

• I have searched Google & GitHub for similar requests and couldn't find anything
• I have read and followed the docs and still think this feature is missing

Description

I was recently asked for a way to require ascii-only text, and couldn't see anything better than requiring a regex accepting the ascii charset range in StringConstraints.

I would think that an ascii_only option (name to be bikeshed) would be more user-friendly. It's potentially also possible to check for ascii-only characters a lot cheaper without using a regex.

Affected Components

• Compatibility between releases
• Data validation/parsing
• Data serialization - .model_dump() and .model_dump_json()
• JSON Schema
• Dataclasses
• Model Config
• Field Types - adding or changing a particular data type
• Function validation decorator
• Generic Models
• Other Model behaviour - model_construct(), pickling, private attributes, ORM mode
• Plugins and integration with other tools - mypy, FastAPI, python-devtools, Hypothesis, VS Code, PyCharm, etc.