Bar states. Built-in variables barstate.*

A set of built-in variables of the barstate namespace allows users to define the bar states for which scripts actions are performed:

• barstate.isfirst - true if the current bar is the first in the whole range of bars available, false otherwise.
• barstate.islast - true if the current bar is the last in the whole range of bars available, false otherwise. This flag helps to detect the last historical bar.
• barstate.ishistory - true if the current data update is a historical bar update, false otherwise (thus it is realtime).
• barstate.isrealtime - true if the current data update is a real-time bar update, false otherwise (thus it is historical). Note that every realtime bar is also the last one.
• barstate.isnew - true if the current data update is the first (opening) update of a new bar, false otherwise.
• barstate.isconfirmed - true if the current data update is the last (closing) update of the current bar, false otherwise. The next data update will be an opening update of a new bar¹.
• barstate.islastconfirmedhistory - true if script is executing on the dataset’s last bar when market is closed, or script is executing on the bar immediately preceding the real-time bar, if market is open. Returns false otherwise.

All historical bars are considered new bars. That is because of the fact that the script receives them in a sequential order from the oldest to the newer ones. For bars that update in realtime, a bar is considered new only at the opening tick of this bar.

Here is an example of a script using barstate.* variables:

We begin by adding the “Bar States” study to a yearly chart and take a screenshot before any realtime update is received. This shows the first and the last bars, and the fact that all bars are new ones:

When a realtime update is received, the picture changes slightly. The current bar is no longer a historical bar, it has become a realtime bar. Additionally, it is neither new nor confirmed, which we indicate with the intra-bar text in the label.

This is a screenshot of the same symbol at a 1 minute timeframe, after a few realtime bars have elapsed. The elapsed realtime bars show the confirmed state.