Crate numscan

numscan

A library to scan for numbers in text.

• A number must have a digit in it.
• A number may have a minus (-) prefix.
• A number may contain digits, dots, and comma.
• A number ends on the first non-numeric character it finds or second dot, and never on comma or dot.
• The library only looks for ASCII digits (in contrast to Arabic numerals etc.)
• Comma separators can be used liberally, they’re mostly ignored.

Examples

use numscan::NumberScanner;

let input = "1.9 - (-1.7) + 1,000 is 1,000.2.";
let output = NumberScanner::from(input).collect::<Vec<_>>();

assert_eq!(
  output,
  [
    0..3,   // "1.9"
    7..11,  // "-1.7"
    15..20, // "1,000"
    24..31, // "1,000.2"
  ]
);

Tip: Parsing

The library returns ranges which you can use for indexing the numbers. In the likely scenario you want to parse them as numbers, keep in mind:

• You might want to use a decimal library, if precision matters at all.
• The strings might contain commas which your number type’s parsing function is likely to not accept, so you might want to remove them before attempting to parse.

Structs

NumberScanner

Scans for numbers.