---
name: "Catmandu::Fix::Condition::is_valid_issn"
section: "3pm"
platform: "linux"
package: "libcatmandu-identifier-perl"
version: "0.15-2"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/Catmandu::Fix::Condition::is_valid_issn"
---

# Catmandu::Fix::Condition::is\_valid\_issn(3pm)

condition on validity of issn numbers

## NAME

Catmandu::Fix::Condition::is\_valid\_issn - condition on validity of issn numbers

## SYNOPSIS

```
   if is_valid_issn(issn_field)
     ...
   else
     ...
   end
```

## SEE ALSO

Catmandu::Fix