src/vs/editor/contrib/wordHighlighter/browser/wordHighlighter.ts/OccurenceAtPositionRequest/isValid
class OccurenceAtPositionRequest:	public isValid(model: ITextModel, selection: Selection, decorationIds: string[]): boolean {

		const lineNumber = selection.startLineNumber;
		const startColumn = selection.startColumn;
		const endColumn = selection.endColumn;
		const currentWordRange = this._getCurrentWordRange(model, selection);

		let requestIsValid = Boolean(this._wordRange && this._wordRange.equalsRange(currentWordRange));

		// Even if we are on a different word, if that word is in the decorations ranges, the request is still valid
		// (Same symbol)
		for (let i = 0, len = decorationIds.length; !requestIsValid && i < len; i++) {
			let range = model.getDecorationRange(decorationIds[i]);
			if (range && range.startLineNumber === lineNumber) {
				if (range.startColumn <= startColumn && range.endColumn >= endColumn) {
					requestIsValid = true;
				}
			}
		}

		return requestIsValid;
	}