Function changeValue

src/FinalForm.ts:247–251

(state, name, mutate)

  };

  const changeValue: ChangeValue<FormValues, InitialFormValues> = (state, name, mutate) => {
    const before = getIn(state.formState.values as object, name);
    const after = mutate(before);
    state.formState.values = (setIn(state.formState.values as object, name, after) || {}) as FormValues;
  };
  const renameField: RenameField<FormValues, InitialFormValues> = (state, from, to) => {
    if (state.fields[from]) {
      state.fields = Object.assign(Object.create(null), state.fields, {