Automated Synthesis of Functional Programs with Auxiliary Functions

  • Shingo Eguchi
  • Naoki KobayashiEmail author
  • Takeshi Tsukada
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 11275)


Polikarpova et al. have recently proposed a method for synthesizing functional programs from specifications expressed as refinement types, and implemented a program synthesis tool Synquid. Although Synquid can generate non-trivial programs on various data structures such as lists and binary search trees, it cannot automatically generate programs that require auxiliary functions, unless users provide the specifications of auxiliary functions. We propose an extension of Synquid to enable automatic synthesis of programs with auxiliary functions. The idea is to prepare a template of the target function containing unknown auxiliary functions, infer the types of auxiliary functions, and then use Synquid to synthesize the auxiliary functions. We have implemented a program synthesizer based on our method, and confirmed through experiments that our method can synthesize several programs with auxiliary functions, which Synquid is unable to automatically synthesize.



We would like to thank anonymous referees for useful comments. This work was supported by JSPS KAKENHI Grant Number JP15H05706 and JP16K16004.

Supplementary material


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© Springer Nature Switzerland AG 2018

Authors and Affiliations

  • Shingo Eguchi
    • 1
  • Naoki Kobayashi
    • 1
    Email author
  • Takeshi Tsukada
    • 1
  1. 1.The University of TokyoTokyoJapan

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