session

How do you find the first bar of each session? Not with session.isfirstbar: this engine doesn't follow sessions bar by bar, so session.ismarket is always true and the other flags are always false. Test the trading day instead, which changes on a session's first bar.

//@version=6
indicator("Each session's open", overlay = true)
// session.isfirstbar is always false here, so watch the trading day change
newDay = ta.change(time_tradingday) != 0
var float dayOpen = na
if newDay
    dayOpen := open
plot(dayOpen, "Session open", color.orange, style = plot.style_stepline)

To test whether a bar sits inside given hours, pass a session to time, which reads na outside it. See sessions.

The session flags never move

A script written for TradingView that waits for session.isfirstbar, session.islastbar or session.ispremarket never acts here, and one that skips bars outside session.ismarket skips none.

session.ismarket

Pine v6No effect here

series bool session.ismarket

Always true here, whatever the bar's hours.

session.is*

No effect here

The other session flags, each always false here.

Each is a series bool.

Name
session.isfirstbar
session.isfirstbar_regular
session.islastbar
session.islastbar_regular
session.ispostmarket
session.ispremarket

session.*

The session kinds, for the session argument of time and time_close.

Each is a const string.

Name	What it means
session.extended	The symbol's extended hours: NYSE's from 04:00 to 20:00 for a symbol on New York's clock, else the same as session.regular.
session.regular	The symbol's regular trading hours.