Compiler Fixes

Fix MQL5 indicator values with handles and CopyBuffer.

In MQL5, indicator functions such as iMA and iRSI usually return an indicator handle. The EA then reads values with CopyBuffer. Treating the call like an MQL4 direct value often creates compile errors or silent signal bugs.

Search intent

The developer gets wrong-parameter, undeclared, or zero-value indicator errors after moving MT4 indicator logic into MQL5.

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Create handles in OnInit

Indicator handles should be created once, checked against INVALID_HANDLE, and reused. Recreating handles on every tick makes debugging harder.

Create iMA/iRSI/iStochastic handles in OnInit

Check INVALID_HANDLE

Release handles in OnDeinit

Read values with CopyBuffer

Use CopyBuffer to pull the current and previous values into arrays. Then make signal decisions from those arrays.

Copy at least two or three bars

Check the copied count

Use ArraySetAsSeries when reading [0] and [1] as current/previous

Separate signal from execution

Once indicator values are valid, the EA still needs spread, session, exposure, stop, and retcode checks before trading.

Signal function

Risk gate

Execution function

Use the tool

Paste the indicator block into Workfusion Debugger to convert MT4-style indicator calls into an MQL5 handle + CopyBuffer flow.

Fix the first error first

Keep full EA context attached

Recompile before changing strategy logic

Open compiler fix desk Open related tool page

Related guides

Continue the EA build path.

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