How to make a trie in Zig

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There are two ways:

  1. allocator as function parameter
pub fn insert(self: *Self, allocator: std.mem.Allocator, word: []const u8) !void {
    ...
    var new_node = try allocator.create(TrieNode);
    ...
}
  1. allocator as member
const Trie = struct {
    allocator: std.mem.Allocator,
    ...
}

pub fn insert(self: *Self, word: []const u8) !void {
    ...
    var new_node = try self.allocator.create(TrieNode);
    ...
}

To get the allocator:

var gpa = std.heap.GeneralPurposeAllocator(.{}){};
const allocator = gpa.allocator();

For each allocator.create you need an allocator.destroy to free memory.

A great allocator tutorial is: Learning Zig - Heap Memory & Allocators
Also note: Allocation is not Initialization

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