Pine Script: Release Notes

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This page contains release notes of notable changes in Pine Script.

2017-05-17: compile-time constants

Pine Script used to have 3 types of constants – literal, non-literal and serial. Now there’s one more, but let’s look at existing ones first.

Some functions (input, color) can only accept literals as certain arguments. We realized that it could be more convenient, so we added a new type of constants that can be calculated during compilation. In addition to literals, they include mathematical expressions that use other literals and constants.

Any type of Pine Script literal (integer, float, boolean, string) is the most specific type while the serial type is the most general one. The compilation-time constants take a spot between the literal and non-literal types. All of the functions that accepted literal as an argument will now accept compilation-time constants as well.

2017-04-26: input with options

Some built-in indicators have a setting that lets you choose several options. The same is possible in Pine Script now.

2017-04-17: kwargs syntax for all builtin functions

Pinescript had different calls for annotation functions (study, plot,…) and built-in functions (sma, security, …). Annotation functions used to accept keyword arguments while built-in functions didn’t.

You are now able to call all built-in functions using keyword arguments. This will be especially useful for the security function to specify the lookahead argument but skip the gaps argument:

security('TSLA', 'D', close, lookahead=barmerge.lookahead_off)

2017-03-20: Pine Version 3

Repainting and backtesting issues have been reported for some time. These issues are not identical, but they are interrelated. Version 3 aims to solve the backtesting issue. Here’s a more detailed explanation.

Repainting issue

There’s a substantial difference between historical and real-time data that a PineScript indicator or strategy uses. The key difference - a historical bar does NOT contain information about price movements between High and Low of a bar. Only a few PineScript language tools are sensitive to this difference:

  • Security - while requesting data of a larger timeframe than a current one .
  • barstate.isrealtime, barstate.ishistory, barstate.islast, barstate.isnew - while using built-in variables
  • While using strategy combined with calc_on_every_tick=true.
  • While using a built-in variable - timenow, n (Doesn’t relate to the historical and real-time data difference, but still causes the “repainting” issue sometimes).

The “repainting” issue usually occurs when using tools above - since an indicator is calculated based on real-time data first. After reloading the chart, an indicator is REcalculated based on data that becomes historical, while still using the same time period. The appearance of the indicator changes.

In this case, the “repainting” effect is not a bug - it’s a result of applying certain language tools with different calculation methods. This needs to be understood and taken into consideration while using PineScript.

Here is a basic example that describes this case:

//@version=2
study("My Script")
a = barstate.isrealtime or barstate.islast ? close : na
plot(a)

The above script is based on historical data and always returns na. It can be plotted only on the last bar of both historical and real-time data. After each chart reload (after pressing F5) the border that divides historical data and real-time will be shifted, in accordance with the current time period.

Backtesting issue

The second issue is a security function that allows you to get “future” data while doing calculations using historical data. For example: security(tickerid, “D”, high) on historical data will show the daily high price on the first hourly bar of the day. This can be used to create an incorrect backtesting strategy:

//@version=2
strategy("Fake strategy", overlay=true)

r = input("D", type=resolution)
l = security(tickerid, r, low)
h = security(tickerid, r, high)

longCondition = low == l
if (longCondition)
    strategy.entry("My Long Entry Id", strategy.long)

shortCondition = high == h
if (shortCondition)
    strategy.entry("My Short Entry Id", strategy.short)

However, we believe that this type of behavior of the security function could be useful when it’s being used in indicators. For instance, ChrisMoody uses this effect in a popular indicator called CM_Pivot Points_M-W-D-4H-1H_Filtered (over 3000 likes) that is used to create pivot lines. Some other examples - Open Close Daily Line, Time Frame Superimpose, as well as the GetSatisfaction comment. We decided that the old behavior will remain available only when it’s expressly indicated.

By default, security function will NOT return future data. This type of behavior will be available by default starting from the PineScript v3 in order to maintain backward compatibility (//@version=3).

We also added a new parameter lookahead with two values: barmerge.lookahead_off and barmerge.lookahead_on to switch between the new and old behavior of the security function. Detailed description of this parameter can be found in pine tutorial chapter on security

Changes of type system

  • Self-referenced and forward-referenced variables are removed
  • No more math operations with booleans

See Migration Guide for more details.