Variables, Constants, and Initial State

Mortar v0.4 introduced workspace-wide state so dialogue can react to progress. All declarations must live at the top level of your script (outside node blocks or functions), which keeps Mortar’s runtime deterministic and easy to serialize.

Declaring Variables

Use let followed by a name, type, and optional initializer. Mortar supports three primitive types: String, Number, and Bool.

let player_name: String
let player_score: Number = 0
let is_live: Bool = true

Key rules:

• No null, default value (empty string, 0, false) will be provided if not assigned.
• Reassignment happens inside nodes: player_score = player_score + 10.
• Keep declarations outside nodes and functions so the compiler can include them in the top-level variables array of the .mortared file.

Every variable becomes a key in the exported JSON, making it trivial for your game to hydrate a hash map or dictionary.

Public Constants for Key-Value Text

Non-dialogue UI strings or configuration can be defined via pub const. These entries are immutable and marked as public in the JSON output so localization pipelines or scripting layers can expose them.

pub const welcome_message: String = "Welcome to the expedition!"
pub const continue_label: String = "Continue"
pub const exit_label: String = "Exit"

Constants are ideal when you need consistent button labels, notifications, or metadata for every language variant.

Runtime Usage

Inside a node you can freely mix variable assignments with text:

node AwardPoints {
    player_score = player_score + 5
    text: $"Score updated: {player_score}"
}

The serializer records those assignments under pre_statements or inline text blocks, ensuring the execution order mirrors the script. Use this mechanism to keep gameplay state close to the dialogue flow without turning Mortar into a general-purpose programming language. For richer domain modeling, pair variables with enums and branch interpolation.