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import Nemathode from 'nemathode';
import { config } from './config';

const nemathode = Nemathode({
    ...config,
});

// method for expression evaluation
const res = nemathode.evaluate([...]);

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...
    '+': {
        precedence: 1,
        implementation: (l: number, r: number): number => {
            return l + r;
        },
    }
...

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const toOutputValue = (val: unknown): number | boolean => {
	if (val instanceof Decimal) {
		return val.toNumber();
	}

	return val;
};

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const toInputType = (val: unknown): Decimal | unknown => {
	if (typeof val === 'number') {
		const input = new Decimal(val);
        
		return input;
	}

	return val;
};

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const config = {
		mathConstants: {
			'E': Math.E,
			'LN2': Math.LN2,
			'LN10': Math.LN10,
			'LOG10E': Math.LOG10E,
			'LOG2E': Math.LOG2E,
			'PI': Math.PI,
			'SQRT1_2': Math.SQRT1_2,
			'SQRT2': Math.SQRT2,

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const resOfNestedExp = nemathode.evaluate([1, '+', 'PI', '*', ['abs', 1, 2, 3], '-', [1, '+', [1, '/', 25]]]);

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const piConst = nemathode.mathConstants.PI;
const piConstInUse = nemathode.evaluate([1, '+', 'PI']);

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const customFunction = nemathode.evaluate([1, '+', ['abs', 1, 2, 3]]); //a rguments are not evaluated (future)
const singleFunction = nemathode.evaluate([['abs', 1, 2, 3]]; // single function syntax (it's not convinient, but for now it's only way)
const boolResult = nemathode.evaluate([['areEqual', 1, 2, 3]]); // returns boolean
// etc

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const sumOperator = nemathode.evaluate([1, '+', 1]); // 2
const mulOperator = nemathode.evaluate([1, '*', 1]); // 1

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const res1 = nemathode.evaluate([0, '+', 1]); // 1
const res2 = nemathode.evaluate([0, '+', 1, '*', [2, '/', 1, '-', 3]); // -1