tags: #js #javascript #data-structure #trie #toy-example #example
## trie.js
```js
class Trie {
constructor() {
this.d = new Map()
}
insert(k,v) {
if( k.length === 0 ) {
this.data = v
return
}
const c = k[0]
if( ! this.d.has(c) ) {
this.d.set(c,new Trie())
}
return this.d.get(c).insert(k.slice(1),v)
}
remove(k) {
// blatant memory leak but
// our intention for this structure
// is that we populate it at page load
// and then no longer modify it.
// so this function shouldn't really
// even be here
const node = this.getNode(k)
if( node.data !== undefined ) {
node.data = undefined
}
}
has(k) {
const node = this.getNode(k)
if( node.data !== undefined ) return true
return false
}
get(k) {
const node = this.getNode(k)
return node?.data
}
getNode(k) {
// inefficient recursive approach
if( k.length === 0 ) return this
const c = k[0]
if( !this.d.has(c) ) return undefined
return this.d.get(c).getNode(k.slice(1))
}
}
```
## Test runner
```html
Document
```