what are handlebars' lambdas and how to use them?

[iamstarkov]

I found it in code https://github.com/handlebars-lang/handlebars.js/blob/master/lib/handlebars/runtime.js#L146-L148 and in README:

The optional Mustache-style lambdas are not supported. Instead Handlebars provides its own lambda resolution that follows the behaviors of helpers.

but there is nothing else in documentation about it.

what are handlebars' lambdas and how to use them?

[jaylinski]

Mustache-style lambdas

// Pseudo code
const template = compile("{{today}}");
template({
  year: 1970,
  today: function() {
    return "Year: {{year}}"
  }
});

Source: https://mustache.github.io/mustache.5.html

Handlebars lambdas

const template = compile("{{today}}");
template({
  year: () => 1970,
  today: function () {
    return `Year: ${this.year()}`;
  }
});

Source:

handlebars.js/spec/helpers.js

Lines 768 to 779 in f422bfd

	it('lambdas resolved by blockHelperMissing are bound to the context', function () {
	expectTemplate('{{#truthy}}yep{{/truthy}}')
	.withInput({
	truthy: function () {
	return this.truthiness();
	},
	truthiness: function () {
	return false;
	},
	})
	.toCompileTo('');
	});

[iamstarkov]

@jaylinski thank you