(add 2) returns a function which takes one parameter - the second parameter in adding something.Functions are called one argument at a time.The :: operator has the lowest precedence, so you need to parenthesize.You can declare the type of a symbol or expression with double colons (" ::").Types Every expression and binding has a type (it is strongly typed) But David Mazieres finds that this can cause difficult to find bugs, so he suggests that you use the longer symbol name for the larger scope. It's conventional in Haskell to have versions of variables and functions denoted by apostrophes (').Convenient for binding variables to use in guards.Where clauses can scope over multiple guards.otherwise in the Haskell system Prelude evaluates to true.Pipe (" |") symbol introduces a guard.Guards let you shorten function declarations by declaring conditions in which a function occurs:.Use an accumulator argument to make the factorial call tail recursive. Solution: Haskell supports optimized tail recursion.Problem: The example recursive factorial implementation in Haskell uses function calls to loop, but those function calls will create stack frames, which will cause Haskell to consume memory.In Haskell, you can use recursion to "re-bind" argument symbols in a new scope (call the function with different arguments to get different behavior).In C, you use mutable variables to create loops (like a for loop).In print x How can you program without mutable variables? Loops This program will cause an infinite loop (the program "diverges"), because the variable x in main is defined in terms of itself, not in terms of the declaration x = 5: x = 5 recursive - bound symbol is in scope within its own definition.so long as you're careful that those don't get evaluated. This means you can divide by 0, create infinite lists.If you divide two variables, for instance, it will not be evaluated until you read the result lazy - definitions of symbols are evaluated only when needed.x = 5 x = 6 is an error, since x cannot be changed.Deterministic - same result every time it is run with an input.By functions, we mean mathematical functions.Associativity - use parentheses for compound expressions.Tokens on the line are function arguments.Haskell will auto-insert semicolons by a layout rule.Not quite a read-execute loop like other languages, but it's useful. Compile it with ghc hello_world.hs, and run the executable. A truly marvelous home near fine dining, shopping & more.Install the Haskell Platform or cabal + ghc. Additional conveniences include an integrated control 4 system & surround sound. The private entertainer’s yard features a cabana, sparkling pool & spa perfect for relaxation or entertaining. Upstairs, the remaining spacious guest bedrooms feature private balconies, beautiful bathrooms, & walk-in closets. The spa-like master bath features dual vanity, soaking tub & rain shower. Upstairs, the romantic master suite showcases a fireplace, interior and exterior spacious balcony overlooking the pool & an incredible walk-in closet. A downstairs en-suite complete the main floor. Oversized pocket sliding glass doors open up the entire family room to the remarkable backyard perfect for indoor/outdoor entertaining. An inviting family room boasts a fireplace and beautiful built-in cabinets. The designer kitchen boasts stone countertops, center island & Miele appliances. A wide entry hall flows into a spacious formal dining room flanked by a wine display and floating staircase. Manicured landscaping invites you into the stunning two-story home, guests are greeted by European oak wood floors, high ceilings, & luxurious finishes throughout. Elegant gated Contemporary Modern Masterpiece in a coveted enclave of Encino.
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