Function isCurrencySymbol

isCurrencySymbol(symbol: unknown): symbol is valueof<{ [key: string]: string }>

Type guard to validate if a value is a valid currency symbol. Checks if the value is a string and if it is in the CURRENCY_SYMBOL_MAP.

Parameters

symbol: unknown
The value to validate

Returns symbol is valueof<{ [key: string]: string }>

Type predicate indicating if the value is a valid currency symbol

Example

const validSymbol = "$";
if (isCurrencySymbol(validSymbol)) {
  console.log("Valid currency symbol:", validSymbol);
} else {
  console.log("Invalid currency symbol:", validSymbol);
}

Source

export function isCurrencySymbol(symbol: unknown): symbol is CurrencySymbol {
  // CURRENCY_SYMBOL_MAP maps code -> symbol, so its values are the valid symbols (e.g. "$").
  return typeof symbol === 'string' && Object.values(CURRENCY_SYMBOL_MAP).includes(symbol);
}