text/template: clarify error when too few or too many return values
Prior to CL 561115, calling a function without any return values would
print "function called with 0 args; should be 1 or 2". Afterwards, the
error message became "too many return values".
Keep the improvement of referring to return values rather than args,
and bring back clarity about their actual and permitted numbers.
Change-Id: I2c014e4633208cc7052fac265a995a8f2fe68151
Reviewed-on: https://go-review.googlesource.com/c/go/+/588355 Reviewed-by: Dmitri Shuralyov <dmitshur@google.com> Reviewed-by: Ian Lance Taylor <iant@google.com>
Auto-Submit: Dmitri Shuralyov <dmitshur@golang.org>
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