What's the best way of doing dynamic filtering?

[kitsunde]

I need to filter a table based on a dynamic filter.

const filters = [
  {column: 'a', min: 0, max: 10},
  {column: 'b', min: 2, max: 7}
]

So since I can't reference it from the outside I pass it into params:

table.params({ filters })

However various ways of looping isn't possible:

table.filter((d, $) => {
  for (const filter of $.filters) {
    // ...
  }
})

For-of loops not allowed

table.filter((d, $) => {
  for (let i = 0; i < $.filters.length; i++) {
    // ...
  }
})

For loops not allowed

And of course, using an array method is also not:

table.filter((d, $) => {
  $.filters.every(() => { /*....*/ });
})

Table expressions do not support closures.

So then I can pass params and call filter individually:

filters.forEach((filter) => {
  table = table.params({filter}).filter((d, $) => { /**/ })
})

Now this works, but I am a bit concerned how this would actually be handled internally, would each filter need to pass over the data one at a time? Would overriding the same attribute repeatedly and then filtering on those properties be wise?

The alternative seem to be:

• Build the filters as a string (seems like the correct option?)
• Escape the function to be able to use closures / loops.
• Build a second table with conditions and do a join against that
• Dynamically add a new function?

[kitsunde]

Additionally, if I build the filters as a string. Is it significantly better to apply all conditions in one large string with many conditions, or does it not matter to call filter multiple times?