Regex timescale validators

[xdmorgan]

Do timescales through pure functions which create regexes for timestamps and filter that way
function returns a generated validator(): bool for 'this month', then filter data: data.filter(validator). Internally, it more or less runs const validator = s => /^2020/.test(s).

• This month - /^2020-05/.test(timestamp)
• Last 90 days - this can be done with regex but it should return a function which does some more involved logic and returns boolean (for filtering)
• Last 6 months - /^2020/.test(timestamp)
• This year - /^2020/.test(timestamp)
• Last year - /^2019/.test(timestamp) (this year - 1)
• All-time - true