---
name: "Text::Roman"
section: "3pm"
platform: "linux"
package: "perl-text-roman"
version: "3.5-14"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/Text::Roman"
---

# Text::Roman(3pm)

Allows conversion between Roman and Arabic algarisms.

## NAME

Text::Roman - Allows conversion between Roman and Arabic algarisms.

## VERSION

version 3.5

## SYNOPSIS

```
    #!/usr/bin/env perl
    use strict;
    use warnings;
    use Text::Roman qw(:all);
    print int2roman(123), "\n";
    my $roman = "XXXV";
    print roman2int($roman), "\n" if isroman($roman);
    my $milhar = 'L_X_XXIII'; # = 60,023
    print milhar2int($milhar), "\n" if ismilhar($milhar);
```

## DESCRIPTION

This package supports both conventional Roman algarisms (which range from *1* to *3999*) and Milhar Romans, a variation which uses a bar across the algarism to indicate multiplication by *1\_000*. For the purposes of this module, acceptable syntax consists of an underscore suffixed to the algarism e.g. IV\_V = *4\_005*. The term Milhar apparently derives from the Portuguese word for "thousands" and the range of this notation extends the range of Roman numbers to *3999 \* 1000 + 3999 = 4\_002\_999*.

Note: the functions in this package treat Roman algarisms in a case-insensitive manner such that "VI" == "vI" == "Vi" == "vi".

The following functions may be imported into the caller package by name:

## FUNCTIONS

### isroman

Tests a string to be a valid Roman algarism. Returns a boolean value.

### int2roman

Converts an integer expressed in Arabic numerals, to its corresponding Roman algarism. If the integer provided is out of the range expressible in Roman notation, an *undef* is returned.

### roman2int

Does the converse of "int2roman", converting a Roman algarism to its integer value.

### ismilhar

Determines whether a string qualifies as a Milhar Roman algarism.

### milhar2int

Converts a Milhar Roman algarism to an integer.

### ismroman/mroman2int/roman

These functions belong to the module's old interface and are considered deprecated. Do not use them in new code and they will eventually be discontinued; they map as follows:

- •

  ismroman      =\> **ismilhar**

- •

  mroman2int    =\> **milhar2int**

- •

  roman         =\> **int2roman**

## CHANGES

Some changes worth noting from this module's previous incarnation:

- *namespace imports*

  The call to **use** must now explicitly request function names imported into it's namespace.

- *argument defaults/void context*

  All functions now will operate on **$\_** when no arguments are passed, and will set **$\_** when called in a void context. This allows for writing code like:

  ```
      @x = qw/V III XI IV/;
      roman2int() for @x;
      print join("-", @x);
  ```

  instead of the uglier:

  ```
      @x = qw/V III XI IV/;
      $_ = roman2int($_) for @x;
      print join("-", @x);
  ```

## SPECIFICATION

Roman algarisms may be described using the following BNF-like formula:

```
    a   = I{1,3}
    b   = V\a?|IV|\a
    e   = X{1,3}\b?|X{0,3}IX|\b
    ee  = IX|\b
    f   = L\e?|XL\ee?|\e
    g   = C{1,3}\f?|C{0,3}XC\ee?|\f
    gg  = XC\ee?|\f
    h   = D\g?|CD\gg?|\g
    j   = M{1,3}\h?|M{0,3}CM\gg?|\h
```

## REFERENCES

For a description of the Roman numeral system see: \<http://www.novaroma.org/via\_romana/numbers.html\>. A reference to Milhar Roman alagarisms (in Portuguese) may be found at: \<http://web.archive.org/web/20020819094718/http://www.estado.com.br/redac/norn-nro.html\>.

## ACKNOWLEDGEMENTS

This module was originally written by Peter de Padua Krauss and submitted to CPAN by Stanislaw Pusep \<https://metacpan.org/author/SYP\> who has relinquished control to Erick Calder \<https://metacpan.org/author/ECALDER\> since the original author has never maintained it and can no longer be reached.

Erick have completely rewritten the module, implementing simpler algorithms to perform the same functionality, adding a test suite, a Changes file, etc. and providing more comprehensive documentation.

Ten years later, Stanislaw returned as a maintainer.

## AUTHOR

Stanislaw Pusep \<stas@sysd.org\>

## COPYRIGHT AND LICENSE

This software is copyright (c) 2003 by Erick Calder \<ecalder@cpan.org\>.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.