Within my `BigNumber` class, the constructor is designed to take an initializing argument that can be a string, number, or another `BigNumber`. Depending on the type of the argument provided, the constructor will initialize an instance of `BigNumber` using the appropriate strategy:
export class BigNumber
{
private static isDecimal = /^(\d+(\.\d*)?|\.\d+)(e[+-]?\d+)?$/i;
public d : number[];
public e : number;
public s : number;
constructor(v : string | number | BigNumber)
{
let e, i, t,
x = this;
if (v instanceof BigNumber)
{
// code for a BigNumber argument
x.s = v.s;
x.e = v.e;
x.d = v.d.slice();
return;
}
else if (typeof v === 'number')
{
// code for a number argument
if (v === 0)
{
x.s = (1 / v < 0) ? -1 : 1;
x.e = 0;
x.d = [0];
return;
}
// Other operations for numbers
}
else if(typeof v === 'string')
{
// code for a string argument
if (v.charCodeAt(0) === 45)
{
v = v.slice(1);
x.s = -1;
}
else
{
x.s = 1;
}
// Other string operations
}
else
{
// throw error
}
}
}
The issue arises when TypeScript generates errors related to assignments or function calls like `slice()` within the string section. It seems that typeguards are not working as expected.
To resolve these errors, explicit casts can be added to each operation. However, I initially believed that the TypeScript compiler could infer the type within an `instanceOf` or `typeof` block. Where might I have made a mistake in this implementation?