HOPE is a programming language created in 1978.
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Hope is a small functional programming language developed in the 1970s at Edinburgh University. It predates Miranda and Haskell and is contemporaneous with ML (also developed at Edinburgh). Hope was derived from NPL, a simple functional language developed by Rod Burstall and John Darlington in their work on program transformation. Read more on Wikipedia...
dec fact : num -> num;
--- fact 0 <= 1;
--- fact n <= n*fact(n-1);
and or not char num div mod dec X # : -> ; --- if then else > <= + ( ) , infix - truval :: nil " <> == in where data ++ lambda
Feature | Supported | Example | Token |
---|---|---|---|
Conditionals | ✓ | ||
Comments | ✓ | --- A comment | |
Line Comments | ✓ | --- A comment | --- |
Single-Type Arrays | ✓ | [1,2,3] | |
Letter-first Identifiers | ✓ | ||
Anonymous Functions | ✓ | lambda(x,y) => x + y | |
Integers | ✓ | ||
Infix Notation | ✓ | max(10,20) + max(1,max(2,3)); | |
Pattern Matching | ✓ | ||
Merges Whitespace | ✓ | ||
hasUserDefinedOperators | ✓ | Hope enables us to use a function with two arguments as an infix operator. e must assign it a priority and use it as an infix operator everywhere, including the equations that define it. A bigger number in the infix declaration means a higher priority. Most of Hope's standard functions are supplied as infix operators. infix mult 8; dec mult : num # num - > num; ---xmulty<= ifY=0then0elsexmult(y-1)+x; | |
Semantic Indentation | X | ||
While Loops | X |