data(){
      return {
        posts: [],
      }
  },
  methods: {
    changeCurrency: function () { // removed unused variable "value" here
      axios.get('http://data.fixer.io/api/latest?access_key=xxxxxx')
      .then(response => {
        this.currency = response.data.rates.value
      })
    },
  }

The parameter value is passed to the changeCurrency function but it is never used in the function itself. Your Linter complains about it due to no-unused-vars rule.

  data(){
      return {
        posts: [],
      }
  },
  methods: {
    changeCurrency: function () { // <-- removed `value` from here. Should pass the linter
      axios.get('http://data.fixer.io/api/latest?access_key=xxxxxx')
      .then(response => {
        this.currency = response.data.rates.value
      })
    },
  }

I want to get in the api with function value and return USD instead of making a lot of functions without value I’m trying this code but compiler returns ‘value’ is defined but never used

any ideas?

  data(){
      return {
        posts: [],
      }
  },
  methods: {
    changeCurrency: function (value) {
      axios.get('http://data.fixer.io/api/latest?access_key=509c9d50c1e92a712be9c8f1f964cf67')
      .then(response => {
        this.currency = response.data.rates.value
      })
    },
  }

    <button @click="changeCurrency(USD)">
      USD
    </button>