Common Lisp the Language
2nd Edition
The block and return-from constructs provide a structured lexical non-local exit facility. At any point lexically within a block construct a return-from with the same name may be used to perform an immediate transfer of control that exits from the block. In the most common cases this mechanism is more efficient than the dynamic non-local exit facility provided by catch and throw described in section 7.11.
[Special Form]
block name {form}*
The block construct executes each form from left to right block name {form}*
The block construct executes each form from left to right=tex2html2582 H