Function setHistogramBrushFilter

packages/tadviewer/src/actions.ts:532–573

(
  colId: string,
  range: [number, number] | null,
  stateRef: StateRef<AppState>
)

};

export const setHistogramBrushFilter = (
  colId: string,
  range: [number, number] | null,
  stateRef: StateRef<AppState>
) => {
  let baseFE: FilterExp;
  if (range !== null) {
    const appState = mutableGet(stateRef);
    const prevFE = appState.viewState.viewParams.filterExp;
    // ensure that prevFE is either null or a top-level "AND" operator:
    if (prevFE != null) {
      if (prevFE.op !== "AND") {
        log.info(
          "setHistogramBrushFilter: unexpected structure for current filter expression, ignoring brush filter"
        );
        return;
      }
      // drop any previous mentions of colId from the filter expression:
      const cleanOpArgs = prevFE.opArgs.filter((subExp: SubExp) => {
        if (subExp.expType === "BinRelExp") {
          const lhs = subExp.lhs;
          if (lhs.expType === "ColRef" && lhs.colName === colId) {
            return false;
          }
        }
        return true;
      });
      baseFE = new FilterExp("AND", cleanOpArgs);
    } else {
      baseFE = and();
    }
    const nextFE = baseFE
      .ge(col(colId), constVal(range[0]))
      .le(col(colId), constVal(range[1]));
    update(
      stateRef,
      vpUpdate(
        (viewParams) => viewParams.set("filterExp", nextFE) as ViewParams
      )
    );
  }
};

export const setHistogramBrushRange = (
  colId: string,