Implementations and Derivatives
No direct implemention of ISWIM was attempted but Art Evan's PAL and John C. Reynolds' Gedanken captured most of Landin's concepts including powerful transfer-of-control operations. Both of these were dynamically typed. Milner's ML may be considered equivalent to I without the J operator and with type inference.
Another line of descent from ISWIM is to strip out the imperative features (assignment and the J operator) leaving a purely functional language. It then becomes possible to switch to lazy evaluation. This path led to programming languages SASL, KRC (Kent Recursive Calculator), Hope, Miranda, Haskell, and Clean.
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