You cannot use variable expressions (such as calls to functions) when setting the initial value of an "extern" or "input" variable/parameter. They are presented to the user before execution begins, so they have to be of a constant nature.
You can however, change the value of "extern" parameters within the EA execution, such as in the OnInit() or OnTick(), but you cannot change "input" variables.
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Hi!
I am, obviously unsuccessfully, trying to paste datetime into string:
This raises an error: '+' - constant expected OmChi EA.mq4 76 101
Adding 'const' before datetime does not solve the issue.
Please advise.
Thank you,
Best regards,
Simon
S love nia