Discussion on: The Idea of Lisp

bcherny profile image
Boris Cherny

Out of curiosity, what's the alternative to if/else? Assuming polymorphism wasn't around in the 50's, did people express the idea of conditional execution based on the result of evaluating some expression using and/or? Does this mean that lazy evaluation was around before conditionals?

ericnormand profile image
Eric Normand Author

Something like you have in assembly: a conditional GOTO that jumps if the argument is equal to zero. Algol actually had a three-way conditional that jumped whether the argument was zero, positive, or negative.