OCaml学习——Substitution-and-Evaluation

Substitution and Evaluation

Implementing OCaml in OCaml Part 2.

Evaluation

Evaluation rewrites the abstact syntax of a program step-by-step until it produces a value.

Example

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(* raw *)
let x = 30 in
let y = 20 + x in
x + y 

->

let y = 20 + 30 in
30 + y

->

let y = 50 in
30 + y

->

30+50

->

80