Struct Form 

pub struct Form { /* private fields */ }

A configuration data structure that is kind-checked at runtime. Items are declared using the item member function, after which their value can be updated but their kind (bool, int, float, string) cannot change.

Implementations

impl Form

pub fn new() -> Form

Creates a blank form.

pub fn item<T: Into<Value>>(self, key: &str, default: T, about: &str) -> Self

Declares a new config item. Any item already declared with that name is replaced.

Arguments

• key - The name of the config item
• default - The default value
• about - A description of the item for use in user reporting

pub fn merge_value_map_freezing( self, items: &HashMap<String, Value>, to_freeze: &[&str], ) -> Result<Self, ConfigError>

Merges in the contents of a string-value map, and freeze any of those items which are named in the given vector of keys to be frozen.

Arguments

• items - A map of values to update the map with
• to_freeze - A vector of keys to freeze, if the key is in items

pub fn merge_value_map( self, items: &HashMap<String, Value>, ) -> Result<Self, ConfigError>

Merges in the contents of a string-value map. The result is an error if any of the new keys have not already been declared in the form, or if they were declared as a different type.

Arguments

• items - A map of values to update the map with

pub fn merge_string_map( self, dict: &HashMap<String, String>, ) -> Result<Self, ConfigError>

Merges in the contents of a string-string map. The result is an error if any of the new keys have not already been declared in the form, or if any of the value strings do not parse to the declared type.

Arguments

• dict - A map of string to update the map with

pub fn merge_string_args<T: IntoIterator<Item = U>, U: Into<String>>( self, args: T, ) -> Result<Self, ConfigError>

Merges in a sequence of “key=value” pairs. The result is an error if any of the new keys have not already been declared in the form, or if any of the value strings do not parse to the declared type.

Arguments

• args - Iterator of string to update the map with

Example

let form = base.merge_string_args(std::env::args().skip(1)).unwrap();

pub fn merge_string_args_allowing_duplicates<T: IntoIterator<Item = U>, U: Into<String>>( self, args: T, ) -> Result<Self, ConfigError>

pub fn freeze(self, key: &str) -> Self

Freezes a parameter with the given name, if it exists, or otherwise panic.

pub fn value_map(&self) -> HashMap<String, Value>

Returns a hash map of the (key, value) items, stripping out the about messages. If the HDF5 feature is enabled, the result can be written directly to an HDF5 group via io::write_to_hdf5.

pub fn iter(&self) -> impl Iterator<Item = (&str, &Value)>

pub fn len(&self) -> usize

Returns the number of items.

pub fn is_empty(&self) -> bool

Returns whether the map is empty.

pub fn sorted_keys(&self) -> Vec<String>

Returns a vector of the keys in this map, sorted alphabetically.

pub fn get(&self, key: &str) -> &Value

Gets an item from the form. Panics if the item was not declared.

Arguments

• key - The key to get

Example

let x: i64 = form.get("counter").into(); // fails unless "counter" is declared has kind i64

pub fn about(&self, key: &str) -> &str

pub fn is_frozen(&self, key: &str) -> bool

Trait Implementations

impl Default for Form

fn default() -> Self

Returns the “default value” for a type.

impl IntoIterator for Form

type Item = <HashMap<String, Parameter> as IntoIterator>::Item

The type of the elements being iterated over.

type IntoIter = <HashMap<String, Parameter> as IntoIterator>::IntoIter

Which kind of iterator are we turning this into?

fn into_iter(self) -> Self::IntoIter

Creates an iterator from a value.