Clones and Tracing

Neil Ernst
nernst@uvic.ca

University of Victoria

2025-08-13

TPS

  • can you be creative with software code?
    • what elements are creative?
    • what elements are hard to automate?

Creativity

1

Clones

  • how would you know if your code (from above) appeared in an ML dataset?
  • (What does it mean to write like Ernest Hemingway?)
  • why do we create clones? Why have you created them?
  • what are the four types of clones?
  • why do we want to find these things?

Recall that there are four levels of code clones:

  • Type I: Identical code fragments except for variations in whitespace (may be also variations in layout) and comments.
  • Type II: Structurally/syntactically identical fragments except for variations in identifiers, literals, types, layout and comments.

cont

  • Type III: Copied fragments with further modifications. Statements can be changed, added or removed in addition to variations in identifiers, literals, types, layout and comments..
  • Type IV: Two or more code fragments that perform the same computation but implemented through different syntactic variants.

Exercise

I’ve uploaded two files to the Teams channel. Each contains a method pair that might be a clone.

With a partner,

  1. load all files into your IDE
  2. read over them so you understand what they do.
  3. identify which pairings, if any, are clones, and why you say that.
  4. Ask an AI tool what it thinks.
  5. for the clones, identify which type they are