Delete a Type Parameter with an Empty Parameter List
Type parameters with empty parameter lists are reported as errors, but you have a quick-fix in GoLand to put it right.
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Type parameters with empty parameter lists are highlighted as errors. So, if you type func printInt[](i int), GoLand will highlight [] because the IDE expects type parameters here. In this case, you can either implement type parameters or delete square brackets. To delete square brackets, try the Delete type parameters quick-fix.
Place the cursor on the empty parameter list ([]), press ⌥⏎ (macOS) / Alt+Enter (Windows/Linux), and select Delete type parameters.