form.pl -- Form handling utilities

This module simplifies handling input from forms in the SWISH interface. The values from a form can be turned into an object using notebook.formData(form). The returned dict may be passed to a predicate inside SWISH.

 validate_form(+Dict, +Fields) is det

Run validate_field/4 on all specified fields, combining the error message. Fields is a list of terms of the form

field(Name, Value, Options)

 validate_field(+Dict, +Field, -Value, +Options) is det

True when Value is a valid value for Field from Dict according to Options. Options is a list of processing steps taken to convert and validate the value. Defined steps are:

alnum

All characters must be alphanumeric

alnum_and_spaces

All characters must be alphanumeric or spaces

atom

Convert input to an atom

string

Convert input to a string

default(Term)

Use Term as value if no value appears in the input.

downcase

Convert input to lower case

email

Input must be a value E-mail address.

url

Input must be a valid absolute URL

url(Scheme)

Input must be a valid absolute URL of type Scheme. Using http also allows for https

float

Value is converted to a floating point number.

integer

Value is converted to an integer.

length>N

The value must have at more than N characters

length>=N

The value must have at least N characters

length=<N

The value must have at most N characters

length<N

The value must have at less than N characters

number

Value is converted to a number (integer or float)

oneof(List)

Input must be a member of List.

password

Input must be a reasonable password.

strip

Strip leading and trailing white space and normalize internal white space to a single space.

term

Input is parsed as a Prolog term

 validate_step(+Step, +Value0, -Value) is semidet[private]

 is_url(?Scheme, +URL) is semidet[private]

True if URL looks like a URL that satisfies Scheme.

 string_value(+String, +Value) is semidet[private]

True if String can be considered the stringified version of Value.

Undocumented predicates

The following predicates are exported, but not or incorrectly documented.

 input_error(Arg1, Arg2)