# dns/ipv4? Predicate: is the string an IPv4 literal? ## Syntax

[dns/ipv4? $s]

## Parameters - `$s` — value to test (string) ## Examples

[dns/ipv4? "10.0.0.1"]   # => true
[dns/ipv4? "::1"]        # => false
[dns/ipv4? "localhost"]  # => false

## Returns `true` when the string parses as an IPv4 literal, else `false`. ## See Also `dns/ip?`, `dns/ipv6?`, `dns/parse`