= cowboy_constraints:int(3) == Name cowboy_constraints:int - Integer constraint == Description Constraint functions implement a number of different operations. [source,erlang] ---- int(forward, Bin) -> {ok, Int} | {error, not_an_integer} Bin :: binary() Int :: integer() ---- Validate and convert the text representation of an integer. [source,erlang] ---- int(reverse, Int) -> {ok, Bin} | {error, not_an_integer} ---- Convert an integer back to its text representation. [source,erlang] ---- int(format_error, Error) -> HumanReadable Error :: {not_an_integer, Bin | Int} HumanReadable :: iolist() ---- Generate a human-readable error message. == Arguments Arguments vary depending on the operation. Constraint functions always take the operation type as first argument, and the value as second argument. == Return value The return value varies depending on the operation. == Changelog * *2.0*: Interface modified to allow for a variety of operations. * *1.0*: Constraint introduced. == Examples This function is not meant to be called directly. == See also link:man:cowboy_constraints(3)[cowboy_constraints(3)], link:man:cowboy_constraints:nonempty(3)[cowboy_constraints:nonempty(3)], link:man:cowboy_router(3)[cowboy_router(3)], link:man:cowboy_req:match_cookies(3)[cowboy_req:match_cookies(3)], link:man:cowboy_req:match_qs(3)[cowboy_req:match_qs(3)]