Is @je legal with a single operand?

Technical Development Specifications
1

According to the Z-machine 1.1 standard:

je

2OP:1 1 je a b c d ?(label)

Jump if a is equal to any of the subsequent operands. (Thus @je a never jumps and @je a b jumps if a = b.)

je with just 1 operand is not permitted.

So what should be the result of @je a? Should it crash/UB (as the last paragraph specifies), or be a no-op (as the paragraph above that specifies)?

2

The last paragraph is correct (according to the clarifications in the 1.1 spec proposal), the ‘never jumps’ bit is left over from the previous wording which I didn’t fix properly at the time.

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