FAQ

FAQ

Why won't DateTime d = ... compile? Imported types take your import alias: t.DateTime d = .... The error says "{typeKeyword}" is not a valid type keyword and never mentions imports, which is why this catches everyone once. Signatures on the reference pages are shown as the library declares them, unqualified, so copying one into your own script produces this.

Why won't format_time take syminfo.timezone? It takes a Zone, which is checked at compile time, where str.format_time takes a string that is not. A UTC default would let a ported call compile cleanly and then silently mislabel every evening New York bar. Use z.to_iana() when you need the string form for a built-in.

Why does next_expiry_after raise on ExpiryKind.VIX? VIX settles at the morning opening auction, so a close-shaped Hour parameter cannot name its moment. Silently ignoring the Hour you passed would be worse than an error. Use next_vix_settlement_after.

Why is there no parse(str, pattern)? The built-ins do not offer one either, ISO covers the formats machine-written dates actually arrive in, and a partial implementation would fail in ways that look like data problems. parse_iso returns na rather than guessing.

Why is there no is_market_open(ms, exchange)? An exchange knows which days trade; a session knows which minutes do. Answering that question needs a session anyway, so you name one: sess.is_open(ms). See Choosing the Right Tool.

if na(k) on a Known never fires. Why? na(Known.UNKNOWN) is false. UNKNOWN is a value, not na. Test k == t.Known.UNKNOWN.

Why does is_holiday say a date trades when I know it does not? You are probably past that calendar's horizon. bool has no room for "not known", so a tabled holiday outside the window reads as an ordinary trading day. Check calendar_through() and ask closed_for_holiday() instead.

Why does 31 January plus one month plus one month differ from plus two months? Clamping loses information, so applying it twice loses it twice. The first gives 28 March, the second 31 March. Both are correct answers to different questions, and java.time behaves the same way.

Why does plus_trading_days(0) not move a date off a holiday? Moving zero days is not a request to fix the date. adjusted(conv, ex) is the one that rolls.

Why does trading_day_of_month return na instead of 0? Zero would be a real ordinal. na means the question has no answer for that date.

Why does time_to_open not return 0 while the session is running? Zero is a real distance, so it cannot also be a flag. It answers the same question either way: how far to the next open.

Why did my session box not shrink on the day after Thanksgiving? The session needs EarlyClose = true and a Cal to read the early close from. new_session raises if you set the flag without a calendar.

Why does my custom session trade through holidays? Session.Cal defaults to na, deliberately. Name a calendar.

b.Month := 3 changed a as well. Why? Pine's user-defined types are reference types, so assignment aliases rather than copies. Use .copy() or a wither. See Value Semantics.

Why can't I write a == b on two DateTimes? == on two UDTs is a type error in Pine, not reference equality. Use equals() for field equality or same_instant() for the moment.

My script checks clean but will not add to the chart. The server-side check does not enforce the 100,256 compiled-token cap, so that is the usual cause. It will not be the import: a library compiles as its own unit and does not spend your script's budget. Look at your own string constants first, at two compiled tokens per character. See Performance and Limits.

holidays_between raised on my range. It refuses spans over 20,000 days rather than silently truncating. Derive the span from what you are drawing, such as the visible range.

Is the FOMC calendar trustworthy? Within its window, fomc_known_from() to fomc_known_through(), it is a transcription of the published schedule. It has no offline oracle, so it is checked structurally: that would catch a mistyped digit or a missing meeting, but not a meeting that moved one day and stayed a Tuesday. Outside the window it answers Known.UNKNOWN.

Does russell_rebalance_day handle the 29 and 30 June exception? No, and it says so. It implements the unmodified last-Friday-in-June rule, so it is a week late for 2018, 2023, 2028 and 2029.

Why is the JPX close 30 minutes early in late 2024? The Tokyo close moved on 2024-11-05 and the library models the close at year granularity. It is a known, deliberate divergence, pinned in the test suite. See Scope and Limitations.

Can I add a time zone? Not from outside. DstRule expresses rules as data so that adding a Zone member is a constant rather than a code path, but no high-level entry point takes a DstRule. Zones outside the enum are out of scope.

Are leap seconds handled? They do not exist in Unix time and are not modelled.

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