When used to invoke ⎕FX, ⎕EC returns only the value of executing ⎕FX and not any of the values representing the kind of statement executed and its success or failure.
]boxing 8
⎕ec '⎕fx ''foo'''
┌→──┐
│foo│
└───┘
⎕ec '⍳3'
┌→──────────────┐
│1 ┌→──┐ ┌→────┐│
│ │0 0│ │1 2 3││
│ └───┘ └─────┘│
└∊──────────────┘
