vuejs filter is not a function error

Question

I've got a very basic array:

specialityTest: [{person:'nurse', text:'text1'}, 
{person:'nurse', text:'text1'}, 
{person:'physician', text:'text1'}, 
{person:'physician', text:'text1'}]

I'm trying to filter this using basic filter function:

      this.specialityTest.filter((person) => {
        return (person =="physician")
      })

and then copy filtered array:

  methods: {
   seedSpeciality(){
      this.nurseListSpeciality2 = JSON.parse(JSON.stringify(this.specialityTest.filter(
      (person) => {
        return (person =="physician")
      })))
  },
 }

and this is not working for me... I've got error:

Uncaught (in promise) TypeError: this.specialityTest.filter is not a function at VueComponent.seedSpeciality (AddOfferDialog.vue?f4fc:1771) at VueComponent.boundFn [as seedSpeciality].

What am I doing wrong here?

edit: I run this function from api call:

  fetchSpecialityArray(){
    this.$http.get('http://127.0.0.1:8000/api/speciality')
      .then(response => response.json())
      .then(result => this.specialityTest = result).then(this.seedSpeciality.bind(this))
  },

Answer 1

For me it works fine.Take a look:

<div id="app">
  <button @click="filter">Filter</button>
</div>

new Vue({
  el: "#app",
  data: {
    specialityTest: [
      {person:'nurse', text:'text1'}, 
      {person:'nurse', text:'text1'}, 
      {person:'physician', text:'text1'}, 
      {person:'physician', text:'text1'}
    ]
  },
  methods: {
    filter() {
        let filtered = this.specialityTest.filter((el) => {
        return (el.person =="physician")
      })
      console.log(filtered)
    }
  }
})

You are looping through array of object with filter function so in each loop you get the object.So if you use el.person == "physician" it will work fine

Take a look to my jsfiddle