How to use [strings.builder]

The reference page of strings.builder has its arguments, constraints and declaration.

Creates a string builder scope. Every [strings.builder.append] invocation found inside it appends its value to the builder, and when the scope ends the value of [strings.builder] becomes the concatenated text. Its children are evaluated as a lambda object, and the slot has no arguments of its own.

strings.builder
   strings.builder.append:"howdy"
   strings.builder.append:" world"
get-value:x:@strings.builder

The above will result in the value of the last node being “howdy world”.