Struct Context

pub struct Context { /* private fields */ }

The struct that holds the context of a template rendering.

Light wrapper around a BTreeMap for easier insertions of Serializable values

Implementations

impl Context

pub fn new() -> Context

Initializes an empty context

pub fn insert<T, S>(&mut self, key: S, val: &T)

where T: Serialize + ?Sized, S: Into<String>,

Converts the val parameter to Value and insert it into the context.

Panics if the serialization fails.

let mut context = tera::Context::new();
context.insert("number_users", &42);

pub fn try_insert<T, S>(&mut self, key: S, val: &T) -> Result<(), Error>

where T: Serialize + ?Sized, S: Into<String>,

Converts the val parameter to Value and insert it into the context.

Returns an error if the serialization fails.

let mut context = Context::new();
// user is an instance of a struct implementing `Serialize`
if let Err(_) = context.try_insert("number_users", &user) {
    // Serialization failed
}

pub fn extend(&mut self, source: Context)

Appends the data of the source parameter to self, overwriting existing keys. The source context will be dropped.

let mut target = Context::new();
target.insert("a", &1);
target.insert("b", &2);
let mut source = Context::new();
source.insert("b", &3);
source.insert("d", &4);
target.extend(source);

pub fn into_json(self) -> Value

Converts the context to a serde_json::Value consuming the context.

pub fn from_value(obj: Value) -> Result<Context, Error>

Takes a serde-json Value and convert it into a Context with no overhead/cloning.

pub fn from_serialize(value: impl Serialize) -> Result<Context, Error>

Takes something that impl Serialize and create a context with it. Meant to be used if you have a hashmap or a struct and don’t want to insert values one by one in the context.

pub fn get(&self, index: &str) -> Option<&Value>

Returns the value at a given key index.

pub fn remove(&mut self, index: &str) -> Option<Value>

Remove a key from the context, returning the value at the key if the key was previously inserted into the context.

pub fn contains_key(&self, index: &str) -> bool

Checks if a value exists at a specific index.

Trait Implementations

impl Clone for Context

fn clone(&self) -> Context

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Context

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl Default for Context

fn default() -> Context

Returns the “default value” for a type.

impl PartialEq for Context

fn eq(&self, other: &Context) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl StructuralPartialEq for Context