{"library":"outlines-core","title":"Outlines-core","description":"Outlines-core is a Python library that provides high-performance, structured text generation capabilities, implemented in Rust. It offers core functionality for building regular expressions from JSON schemas and constructing finite-state automata to efficiently guide large language model (LLM) token generation. The current version is 0.2.14, with a release cadence that appears active, aligning with the broader 'outlines' project.","language":"python","status":"active","last_verified":"Wed May 13","install":{"commands":["pip install outlines-core"],"cli":null},"imports":["from outlines_core.json_schema import build_regex_from_schema","from outlines_core.guide import Guide","from outlines_core.guide import Index","from outlines_core.guide import Vocabulary"],"auth":{"required":false,"env_vars":[]},"quickstart":{"code":"import json\nfrom outlines_core.json_schema import build_regex_from_schema\nfrom outlines_core.guide import Guide, Index, Vocabulary\n\n# Define a JSON schema\nschema = {\n    \"title\": \"Foo\",\n    \"type\": \"object\",\n    \"properties\": {\n        \"name\": {\"type\": \"string\"},\n        \"age\": {\"type\": \"integer\"}\n    },\n    \"required\": [\"name\", \"age\"]\n}\n\n# Generate a regular expression from the schema\nregex = build_regex_from_schema(json.dumps(schema))\n\n# Create Vocabulary from a pretrained model (e.g., GPT-2 for demonstration)\nvocabulary = Vocabulary.from_pretrained(\"openai-community/gpt2\")\n\n# Create an Index from the regex and vocabulary\nindex = Index(regex, vocabulary)\n\n# Create a Guide instance\nguide = Guide(index)\n\n# Example interaction with the guide (simplified for quickstart)\n# In a real scenario, you'd integrate this with an LLM's token generation\ncurrent_state = guide.get_state()\nallowed_tokens = guide.get_tokens()\nprint(f\"Initial allowed token IDs: {allowed_tokens}\")\n\n# Simulate advancing the guide with a token (e.g., the first allowed token)\nif allowed_tokens:\n    first_token_id = allowed_tokens[0]\n    # In a real LLM integration, you'd feed this token to the model\n    # and then get the next state based on the model's output.\n    next_allowed_tokens = guide.advance(first_token_id)\n    print(f\"Next allowed token IDs after advancing with {first_token_id}: {next_allowed_tokens}\")\n\nprint(f\"Is guide finished? {guide.is_finished()}\")","lang":"python","description":"This quickstart demonstrates how to use `outlines-core` to build a regular expression from a JSON schema, create a vocabulary from a pretrained model, construct an index, and initialize a `Guide` for structured generation. 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