Assertion to check for the pulses of the clock

[b]In reply to ben@SystemVerilog.us:

In reply to Lina.Lin:
Wouldn’t that cause the miss of $fell(scan_en)
Ben SystemVerilog.us

adding scan_en to disable condition wouldn’t cause the miss of $fell(scan_en) because expression in iff condition uses scan_en current value (not sampled value).