zemplate

A very basic, zero-dependency templating engine written in Zig.

I originally wrote this for my portfolio site, but had a good time doing it so I turned it into its own project.

It currently supports basic interpolation — inserting values from a context struct into a template. Eventually, I’d like to add simple control flow (loops, conditionals), but the goal is to keep it small and simple. Improvements such as these will be implemented as I find I need them for my portfolio.

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Example Usage

const std = @import("std");
const allocator = std.testing.allocator;
const TestTmpl = zemplate.Template(struct { field: []const u8 });
var tmpl = TestTmpl.init(.{ .field = "World" });

const render = try tmpl.render(allocator,
    \\ Hello ||zz .field zz||!
, .{});

defer allocator.free(render);
std.debug.print("{s}", .{ render.items });

The output would be: "Hello World!"

Json Serialization

There is also support for serializing fields as JSON, this is a newer feature and may have some bugs.

const std = @import("std");
const allocator = std.testing.allocator;
const TestTmpl = zemplate.Template(struct { field: struct{key: u32} });
var tmpl = TestTmpl.init(.{ .field = .{ .key = 42 } });
const render = try tmpl.render(
    allocator,
    \\Hello ||zz .field json zz||!
, .{});
defer allocator.free(render);

std.debug.print("{s}", .{ render });

The output would be: "Hello { "key": 42 }!"

Notes

• Fields that you would like to render in your template from your context type must be []const u8, []u8, or ArrayList(u8), otherwise the keyword json must be used in order to render the field.
• For owned fields ([]u8 or ArrayList(u8)), implement a deinit method on your context.

Todos

• Associate templates with any struct, control template rendering via struct fields
• Basic string interpolation
• Json Rendering
• For loops
• If statements
• Template Context method access
• Optimization