Papers › LambdaBeam: Neural Program Search with Higher-Order Functions and Lambdas

LambdaBeam: Neural Program Search with Higher-Order Functions and Lambdas

3 Jun 2023NeurIPS 2023 11arXiv:2306.02049archive 2025-07-28

Search is an important technique in program synthesis that allows for adaptive strategies such as focusing on particular search directions based on execution results. Several prior works have demonstrated that neural models are effective at guiding program synthesis searches. However, a common drawback of those approaches is the inability to handle iterative loops, higher-order functions, or lambda functions, thus limiting prior neural searches from synthesizing longer and more general programs. We address this gap by designing a search algorithm called LambdaBeam that can construct arbitrary lambda functions that compose operations within a given DSL. We create semantic vector representations of the execution behavior of the lambda functions and train a neural policy network to choose which lambdas to construct during search, and pass them as arguments to higher-order functions to perform looping computations. Our experiments show that LambdaBeam outperforms neural, symbolic, and LLM-based techniques in an integer list manipulation domain.

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compute_example_signature ellisk42/lambdabeam/lambdabeam/algorithm/property_signatures.py community (archive-listed) unverified Apache-2.0 (permissive) · 05e00ea04f0b2145 · report
compute_value_signature ellisk42/lambdabeam/lambdabeam/algorithm/property_signatures.py community (archive-listed) unverified Apache-2.0 (permissive) · 5900b8381a2175b5 · report
generate_partitions ellisk42/lambdabeam/lambdabeam/algorithm/baseline_enumeration.py community (archive-listed) unverified Apache-2.0 (permissive) · 16d2ed61bce1cb76 · report
get_int_mapped ellisk42/lambdabeam/lambdabeam/model/encoder.py community (archive-listed) unverified Apache-2.0 (permissive) · 99f6727919426a80 · report
get_pad ellisk42/lambdabeam/lambdabeam/model/encoder.py community (archive-listed) unverified Apache-2.0 (permissive) · 1fc957c1eb03370c · report
pad_sequence ellisk42/lambdabeam/lambdabeam/model/base.py community (archive-listed) unverified Apache-2.0 (permissive) · 6a92b8c8f6066e6d · report
update_masks ellisk42/lambdabeam/lambdabeam/algorithm/synthesis.py community (archive-listed) unverified Apache-2.0 (permissive) · 39fa178f536052cb · report

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