Basics & syntax

Goblin script is an outline language: what's indented under something belongs to it. There are four kinds of named top-level block — Enum, Sheet, Template, and Card — plus global let values. They can appear in any order (forward references work).

Indentation is structure#

Template: MonsterFront
  Rectangle: "Banner"
    x: 0
    color: teal

The Rectangle belongs to the template; x and color belong to the rectangle. Use spaces or tabs, but be consistent within a file.

Comments#

# starts a comment that runs to the end of the line.

# the monster deck — suits come from the loop
Enum: Suit
  case Rock     # beats scissors

One quirk: # followed by exactly six hex digits is a color, not a comment (#ff0000). Don't start a comment with something like #ff0000.

Names#

Declared names — Suit, Monsters, MonsterFront — are plain words: a letter, then letters, digits, or underscores. No quotes.

A small set of words is reserved and can't be used as names: the block openers (Enum Sheet Template Card Rectangle Text TextBox Icon Image Qr Repeat Front Back), the declaration words (case column), and the expression words (if then else and or not as).

Everything else is fair game. Property words like count, size, color, and full are ordinary identifiers — so column count: Number is perfectly legal, and [count] reads that column. Meaning comes from position, and [brackets] always mean a data reference.

Several newer forms are contextual, not reserved names: let is special only in let name: value, param only in param name: Type directly inside a Template, virtual only in virtual column name: Type = expression inside a Sheet, and capitalized If:/Else: only where a Template node can appear. column let: Text, column param: Text, column virtual: Text, Template: If, and Front: If are therefore still legal.

Labels#

The quoted string after a shape is an optional label, purely for your own readability. It's never referenced by anything:

Rectangle: "Banner"      # labelled
Rectangle:               # unlabelled — identical behaviour

Values can span lines#

A property's value may continue onto following lines as long as they're indented deeper than the property name:

color: if [current_suit] == Suit.Rock then grey
       else if [current_suit] == Suit.Paper then gold
       else mediumpurple

This works for property lines (including explicit Template call arguments) and let name: initializers. Block headers like Repeat: and If: never continue — their indented lines are children, so their expressions have to fit on one line.

Data references#

Square brackets always mean look this value up:

text: [name]
x: 1.5 + [i] * 2
text: "Cost: [cost]"     # interpolated inside a string
text: "Card [card:03]"   # Number zero-padded to a minimum width of 3

Where those values come from is Sheets and data, including the Number-only [name:0N] interpolation format. To write a literal [ inside a string, double it: [[.