parseint-loudfail/README.md

If this parseInt() encounters an invalid digit, it fails loudly instead of returning a partially parsed number.

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parseint-loudfail
=================
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If this parseInt() encounters an invalid digit, it fails loudly instead of
returning a partially parsed number.
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API
---

This module exports one function:

### parseIntLoudFail(digits, radix[, invalid])

* `digits` must me a string that consist of optional whitespace,
  then an optional sign (`+` or `-`), then some obligatory digits.
* `radix` must be an integer in range 2..36.
* If `invalid` is provided and `!== 0` and an error occurs,
  `invalid` is returned instead of throwing the error.
* If successful, returns the integer represented by `digits` as a `Number`.



Usage
-----

from [test/usage.js](test/usage.js):

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```javascript
var pInt = require('parseint-loudfail'), eq = require('assert').strictEqual;

eq(pInt('0',     8),     0);
eq(pInt('644',   8),   420);
eq(pInt('644',  10),   644);
eq(pInt('644',  16),  1604);

eq(pInt('06fF', 16, false),  1791);
eq(pInt('06Zz', 16, false),  false);
eq(pInt('',     16, false),  false);
eq(pInt('644',   1, false),  false);

pInt = err2str(pInt);
eq(pInt('',   16),  'Error: Number needs at least one digit.');
eq(pInt('',   0),   'Error: Radix must be an integer in range 2..36.');
eq(pInt('',   1),   'Error: Radix must be an integer in range 2..36.');
eq(pInt('',   99),  'Error: Radix must be an integer in range 2..36.');
eq(pInt('0779',  8),  'Error: Invalid digit "9" for radix 8');
eq(pInt('06Zz', 16),  'Error: Invalid digit "Z" for radix 16');
eq(pInt(644,    10),  'Error: Digits must be given as a string.');

eq(pInt('+0',    8),     0);
eq(pInt('+644',  8),   420);
eq(pInt('+644', 10),   644);
eq(pInt('+644', 16),  1604);

eq(pInt('-0',    8),     0);
eq(pInt('-644',  8),  -420);
eq(pInt('-644', 10),  -644);
eq(pInt('-644', 16), -1604);

eq((1 / pInt('+0', 8)), Number.POSITIVE_INFINITY);
eq((1 / pInt(' 0', 8)), Number.POSITIVE_INFINITY);
eq((1 / pInt('-0', 8)), Number.NEGATIVE_INFINITY);
eq(pInt('\r \t\f\n 644', 8),   420);
eq(pInt('   ', 4),  'Error: Number needs at least one digit.');
eq(pInt('  +', 4),  'Error: Number needs at least one digit.');
eq(pInt(' + ', 4),  'Error: Invalid digit " " for radix 4');
eq(pInt('  -', 4),  'Error: Number needs at least one digit.');
eq(pInt(' - ', 4),  'Error: Invalid digit " " for radix 4');
```
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License
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ISC
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