Factorio Prototype DocsVersion 1.1.107

Evaluates and returns the value of its expression property, which is itself an expression.

This hints to the compiler that it should break the subexpression into its own procedure so that the result can be re-used in multiple places. For instance if you want to re-use the same multioctave noise for determining probability of multiple tiles/entities, wrap the multioctave noise expression in a procedure-delimiter. Alternatively, make the noise its own NamedNoiseExpression and reference it by name, using a NoiseVariable.