Setting a string as "encode" doesn't work (confusing document?)

[mikecat]

The "Index Options" section in the README.md has this as Values for encode Option:

false
"default"
"simple"
"balance"
"advanced"
"extra"
function(str) => [words]

Reading this, I thought that we can set false, one of the strings, or a function as the encode option.

However, setting false worked, but setting strings didn't work.

I tried this code on RunKit:

const FlexSearch = require("flexsearch@0.7.31")

const index = new FlexSearch.Index({
  encode: "simple",
});

index.add(0, "Lorem ipsum dolor sit amet.");

This resulted in an error:

TypeError: this.encode is not a function

at t.add in flexsearch@0.7.31/dist/flexsearch/bundle.js — line 12