[Solved] ENE4014-Homework 3

Exercise 1 Consider the following programming language, called miniML, that features (recursive) procedures and explicit references.

Syntax The syntax is defined as follows:

Semantics The semantics is defined with the following domain:

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and evaluation rules:

,₀ 0,₁ ,₀

,₀ ` iszero E true,<sub>1</sub> ,<sub>0</sub> ` iszero

,₀ ` E<sub>1</sub> true,<sub>1</sub> ,<sub>1</sub> ` E₂ v,₂

,₀ ` if E₁ then E₂ else E₃ v,₂

,₀ ` E<sub>1</sub> false,<sub>1</sub> ,<sub>1</sub> ` E₃ v,₂

,₀ ` if E₁ then E₂ else E₃ v,₂

,₀ ` E<sub>1</sub> v<sub>1</sub>,<sub>1</sub> [x 7 v<sub>1</sub>],<sub>1</sub> ` E₂ v,₂

,₀ ` let x = E₁ in E₂ v,₂

[f 7 (f,x,E₁,)],₀ ` E₂ v,₁

, ` letrec f(x) = E in E v, , ` proc x E (x,E,),

Dom(₁)

,₀ ` E v,₁

,₀ ` begin E end v,₁

Implement an interpreter of miniML. Raise an exception UndefinedSemantics whenever the semantics is undefined. Skeleton code will be provided (before you start, see README.md).

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