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f0743f4 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 | /**
* Evaluates a mathematical expression provided as a string and returns the result.
*
* If the input is already a number, it returns the number as is.
* If the input is not a string or contains invalid characters, an error is thrown.
* If the evaluated result is not a number, an error is thrown.
*
* @param str - The mathematical expression to evaluate, or a number.
* @param fallbackValue - The default value to return if the input is not a string or number, or if the evaluated result is not a number.
*
* @returns The result of the evaluated expression or the input number.
*
* @throws Throws an error if the input is not a string or number, contains invalid characters, or does not evaluate to a number.
*/
export function math(str: string | number | undefined, fallbackValue?: number): number {
const fallback = fallbackValue != null;
if (typeof str !== 'string' && typeof str === 'number') {
return str;
} else if (typeof str !== 'string') {
if (fallback) {
return fallbackValue;
}
throw new Error(`str is ${typeof str}, but should be a string`);
}
const validStr = /^[+\-\d.\s*/%()]+$/.test(str);
if (!validStr) {
if (fallback) {
return fallbackValue;
}
throw new Error('Invalid characters in string');
}
const value = eval(str);
if (typeof value !== 'number') {
if (fallback) {
return fallbackValue;
}
throw new Error(`[math] str did not evaluate to a number but to a ${typeof value}`);
}
return value;
}
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