Text Placeholder
A minimal text template engine that allows named placeholders within your templates.
There are two necessary pieces in order to parse a template:
- Placeholders
- Context
Placeholders
Placeholders are defined within certain boundaries and will be replaced once the template is parsed.
Let's define a template with placeholders named first
and second
:
let template = new;
Templates use the handlebars syntax as boundaries by default, but can be overridden:
let template = new_with_placeholder;
Context
Context is the data structure that will be used to replace your placeholders with real data.
You can think of your placeholder as a key within a HashMap
or the name of a field within a
struct
. In fact, these are the two types of context supported by this library:
- HashMap.
- Struct, as an optional feature.
HashMap
Each placeholder should be a key
with an associated value
that can be converted into a str
.
The following methods are available with a HashMap
:
fill_with_hashmap
- replaces missing placeholders with an empty string.
- replaces placeholders that cannot be converted to a strint with an empty string.
fill_with_hashmap_strict
which returns aError::PlaceholderError
when:- a placeholder is missing.
- a placeholder value cannot be converted to a string.
Example
use Template;
use HashMap;
let default_template = new;
let mut table = new;
table.insert;
table.insert;
assert_eq!;
// We can also specify our own boundaries:
let custom_template = new_with_placeholder;
assert_eq!;
Struct
Allow structs that implement the serde::Serialize
trait to be used as context.
This is an optional feature that depends on serde
. In order to enable it add the following to your Cargo.toml
file:
[]
= { = "0.4", = ["struct_context"] }
Each placeholder should be a field
in your struct
with an associated value
that can be converted into a str
.
The following methods are available with a struct
:
fill_with_struct
- replaces missing placeholders with an empty string.
- replaces placeholders that cannot be converted to a strint with an empty string.
fill_with_struct_strict
which returns aError::PlaceholderError
when:- a placeholder is missing.
- a placeholder value cannot be converted to a string.
Example
use Template;
let default_template = new;
let context = Context ;
assert_eq!;
// We can also specify our own boundaries:
let custom_template = new_with_placeholder;
assert_eq!;