Haskell代写代考

Microsoft PowerPoint – Week2.pptx 2022‐09‐14 Copyright By PowCoder代写 加微信 powcoder Ch 1: Starting Out Ch 2: Believe the Type University of the Fraser Valley COMP 481: Functional and Logic Programming Terminology • referential transparency—guarantees a function returns the  same result when called with the same parameter values • lazy—Haskell will not calculate values until necessary (allows you to make seemingly infinite data structures) • statically typed—all things are determined at compile time • type inference—can let Haskell determine what type something  belongs to, but can still state the type of something if you want 2022‐09‐14 —Math Operations — Typical addition, subtraction, multiplication, division • floating point division / • integer division, e.g.:  div 10 4 evaluates to  2 and not 2.5 • 12 mod 7 • True && False • True || False • not True Comparison •

8. Tree grammars 1 Review: Stringsets and string grammars The kind of thing we’ve done with strings many times now follows this pattern: (1) a. Identify an alphabet of symbols; call it Σ. b. This determines a certain set of strings over this alphabet; usually written Σ∗. c. Identify some subset of Σ∗ as the

1. Expressions, variables and substitution An expression (or term) is a piece of code, or a program. Examples include 3, 3 + 4, “hello” and x * 3. We’ll build up our understanding of Haskell by focussing on two questions: • How are complex expressions built up out of smaller expressions? • What (other expression)