Struct handlebars::Helper

source ·
pub struct Helper<'reg, 'rc> { /* private fields */ }
Expand description

Render-time Helper data when using in a helper definition

Implementations§

source§

impl<'reg: 'rc, 'rc> Helper<'reg, 'rc>

source

pub fn name(&self) -> &str

Returns helper name

source

pub fn params(&self) -> &Vec<PathAndJson<'reg, 'rc>>

Returns all helper params, resolved within the context

source

pub fn param(&self, idx: usize) -> Option<&PathAndJson<'reg, 'rc>>

Returns nth helper param, resolved within the context.

Example

To get the first param in {{my_helper abc}} or {{my_helper 2}}, use h.param(0) in helper definition. Variable abc is auto resolved in current context.

use handlebars::*;

fn my_helper(h: &Helper, rc: &mut RenderContext) -> Result<(), RenderError> {
    let v = h.param(0).map(|v| v.value())
        .ok_or(RenderError::new("param not found"));
    // ..
    Ok(())
}
source

pub fn hash(&self) -> &BTreeMap<&'reg str, PathAndJson<'reg, 'rc>>

Returns hash, resolved within the context

source

pub fn hash_get(&self, key: &str) -> Option<&PathAndJson<'reg, 'rc>>

Return hash value of a given key, resolved within the context

Example

To get the first param in {{my_helper v=abc}} or {{my_helper v=2}}, use h.hash_get("v") in helper definition. Variable abc is auto resolved in current context.

use handlebars::*;

fn my_helper(h: &Helper, rc: &mut RenderContext) -> Result<(), RenderError> {
    let v = h.hash_get("v").map(|v| v.value())
        .ok_or(RenderError::new("param not found"));
    // ..
    Ok(())
}
source

pub fn template(&self) -> Option<&'reg Template>

Returns the default inner template if the helper is a block helper.

Typically you will render the template via: template.render(registry, render_context)

source

pub fn inverse(&self) -> Option<&'reg Template>

Returns the template of else branch if any

source

pub fn is_block(&self) -> bool

Returns if the helper is a block one {{#helper}}{{/helper}} or not {{helper 123}}

source

pub fn has_block_param(&self) -> bool

Returns if the helper has either a block param or block param pair

source

pub fn block_param(&self) -> Option<&'reg str>

Returns block param if any

source

pub fn block_param_pair(&self) -> Option<(&'reg str, &'reg str)>

Return block param pair (for example |key, val|) if any

Trait Implementations§

source§

impl<'reg, 'rc> Debug for Helper<'reg, 'rc>

source§

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

Formats the value using the given formatter. Read more

Auto Trait Implementations§

§

impl<'reg, 'rc> RefUnwindSafe for Helper<'reg, 'rc>

§

impl<'reg, 'rc> Send for Helper<'reg, 'rc>

§

impl<'reg, 'rc> Sync for Helper<'reg, 'rc>

§

impl<'reg, 'rc> Unpin for Helper<'reg, 'rc>

§

impl<'reg, 'rc> UnwindSafe for Helper<'reg, 'rc>

Blanket Implementations§

source§

impl<T> Any for Twhere T: 'static + ?Sized,

source§

fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more
source§

impl<T> Borrow<T> for Twhere T: ?Sized,

source§

fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more
source§

impl<T> BorrowMut<T> for Twhere T: ?Sized,

source§

fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value. Read more
source§

impl<T> From<T> for T

source§

fn from(t: T) -> T

Returns the argument unchanged.

source§

impl<T, U> Into<U> for Twhere U: From<T>,

source§

fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

source§

impl<T> Same<T> for T

§

type Output = T

Should always be Self
source§

impl<T, U> TryFrom<U> for Twhere U: Into<T>,

§

type Error = Infallible

The type returned in the event of a conversion error.
source§

fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

Performs the conversion.
source§

impl<T, U> TryInto<U> for Twhere U: TryFrom<T>,

§

type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.
source§

fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

Performs the conversion.