51 lines
1.1 KiB
JavaScript
51 lines
1.1 KiB
JavaScript
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class Expression {
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constructor(op, left, right) {
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this.op = op
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this.left = left
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this.right = right
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}
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eval() {
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return evalExpression(this)
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}
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}
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function evalExpression(expr) {
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let tempLeft
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let tempRight
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if (typeof(expr.left) === "object") { // Check if left type is another expression
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tempLeft = evalExpression(expr.left)
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}
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else {
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tempLeft = expr.left
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}
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if (typeof(expr.right) === "object") { // Check if right type is another expression
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tempRight = evalExpression(expr.right)
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}
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else {
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tempRight = expr.right
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}
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if (typeof(tempLeft) === "number" & typeof(tempRight) === "number") { // Make sure both inputs are number
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if (expr.op === "+") {
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return tempLeft + tempRight
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}
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else if(expr.op === "-") {
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return tempLeft - tempRight
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}
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else if(expr.op === "*") {
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return tempLeft * tempRight
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}
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else if(expr.op === "/") {
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return tempLeft / tempRight
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}
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else { // Case for when there is no valid provided operator
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return "Invalid operator syntax"
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}
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}
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else { //Case for when the left or right are not numbers
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return "Invalid number syntax"
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}
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}
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exports.Expression = Expression;
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