Non V-bind part of the V-Model - vue.js

Question

As we know v-model is two way binding. Which means it's combination of V-bind and maybe another attribute which I'm looking for and it updates the data. I have a input which it's value is sometimes custom and sometimes should be read from config based on another parameters.
What I need is an input with a v-bind:value/:value and another for update. I know I can do it with #change and a custom method But I'm looking for something easy, Bottom line is I want V-model without doing v-bind ! Thank You
EDIT: I did it with two input using v-if .
<input type="number" class="item-input" v-if="setting.keto_program=='custom'" id="protein_per_kilo" v-model="setting.keto_program_protein_density">
<input type="number" class="item-input" v-else disabled id="protein_per_kilo" :value="config.keto_programs[setting.keto_program].protein_density">
Anyway doing this using just one input feels better. Thanks

Answer 1

May be you can use computed hook.
computed:{
yourVariable(){
return someVariable/computation
}
}
you can use yourVariable inside your code that will act like v-model without doing v-bind.
yourVariable will be updated as soon as the variables of the return statement of this be changed or updated
Edited:
part of v-model for input tag
<input
v-bind:value="variable"
v-on:input="variable = $event.target.value"
>
or
<input
:value="variable"
#input="variable = $event.target.value"
>
found this via
Vue.js—Difference between v-model and v-bind