Pine ScriptJun 12, 20265 min read9 views

Pine Script 'Could Not Find Function' Error: Why It Happens and How to Fix It

The 'could not find function or function reference' error almost always means one thing: v4/v5 syntax in a v6 script. Here's the fix for every common case.

What this error really means

When TradingView says 'Could not find function or function reference', it almost always means you're calling a function that existed in an older Pine version but was renamed or moved in v6. The code looks right because it WAS right — three years ago.

Pine Script v6 namespaced nearly every built-in. Bare function names like sma() and rsi() no longer exist; they live under ta. now.

The fixes, by function

Here are the most common offenders and their v6 replacements:

  • sma(), ema(), rsi(), atr(), macd() → ta.sma(), ta.ema(), ta.rsi(), ta.atr(), ta.macd()
  • crossover(), crossunder() → ta.crossover(), ta.crossunder()
  • highest(), lowest() → ta.highest(), ta.lowest()
  • security() → request.security()
  • study() → indicator()
  • valuewhen(), barssince() → ta.valuewhen(), ta.barssince()

Tip

Paste broken code into TradePilot's Fix mode and it rewrites every legacy call to the correct v6 namespace in one pass — no manual find-and-replace.

Why AI tools cause this

ChatGPT and other general models were trained on years of Pine Script that's mostly v4 and v5. So they default to the old syntax. That's why generic AI output throws this error constantly — and why a v6-specialist tool doesn't.

TP

TradePilot Team

Traders and engineers building the fastest way to go from idea to live Pine Script strategy, right inside TradingView.

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