assignment-terrible-editor/app/codemirror/src/line/saw_special_spans.js

// Optimize some code when these features are not used.
export let sawReadOnlySpans = false, sawCollapsedSpans = false

export function seeReadOnlySpans() {
  sawReadOnlySpans = true
}

export function seeCollapsedSpans() {
  sawCollapsedSpans = true
}