... An identifier can be any identifier accepted by Clean, including operator
notations. For literals characters, strings, integer or floating-point numbers
and boolean values are accepted.
We illustrate the use of Sapl by giving a number of examples. We start with
the encoding of the list data type, to ...
Compiling Purely Functional Structured Programs
... depending on whether we evaluate the outer application
right-to-left or left-to-right.
Compilation of functional programs via CPS transformation was the basis for the classic text Compiling with Continuations , but the approach has notoriously fallen out
of favour. Compiler toolchains such as LLV ...
Programming with Coq
... match x with 0 => 1 | S p => x * fact p end
This simple schema only for natural numbers ! More complex
schemas for other datatypes.
An introduction to C++ template programming
... might even output the result in compiler error messages for extra strangeness.
However, in the latest C++11 standard, constexpr functions already provide
compile-time functional computation. Here we will put greater emphasis to the
relation of templates to type parametrization than their compile-tim ...
... Functional programming
Functional programming is a style of programming that
emphasizes the evaluation of expressions, rather than
execution of commands. The expressions in these languages
are formed by using functions to combine basic values.
[Hutton ed. 2002]
Introduction to Imperative C Functional vs. imperative programming
... An expression with a side effect does more than produce a value: it
also changes the state of the program (or “the world”).
Functions (or programs) can also have side effects.
We have already seen a C function with a side effect: printf.
The side effect of printf is that it displays “output”. In oth ...
Order of Growth - inst.eecs.berkeley.edu
... As we saw in lecture, calc was a program that let us define a very simple language and interpret it much like the Python
interpreter. The program spends most of its time in the read-eval-print-loop (often called a REPL), which continuously
reads a line of input, translates this into an expression ob ...
... is everywhere.
In Haskell, the programmer can choose when to live in
the IO monad and when to live in the realm of pure
Interesting perspective: It is not Haskell that lacks
imperative features, but rather the other languages that
lack the ability to have a statically dis ...
... languages don’t control where effects occur.
What happens if code outside a transaction
conflicts with code inside a transaction?
Weak Atomicity: Non-transactional code can see
inconsistent memory states. Programmer should
avoid such situations by placing all accesses to
shared state in transactio ...
shown in an prompt box
have shown in the input box
the user closed the prompt dialog box
Transformat ions on higher
... and others are not. To be able to exploit this
we shall introduce an explicit distinction between
known and unknown values or, using traditional
compiler terminology, between compile-time
entities and run-time entities. This leads to the following approach to the implementation
Design and Evaluation of Gradual Typing for Python
... Reticulated, this choice is made in function definitions, where parameter and return types can be specified, and in class definitions,
where we use Python decorators to specify the types of object
fields. When no type annotation is given for a parameter or object
field, Reticulated gives it the dyna ...
PolyP | a polytypic programming language extension
... they work for large classes of datatypes.
Consider for example the function length :: List
a -> Int, which counts the number of values of type
a in a list. There is a very similar function length
:: Tree a -> Int, which counts the number of occurrences of a's in a tree. We now want to generalise
Table of contents
... The functions alluded to in the title are mathematical functions. Mathematical functions have
great strengths in terms of flexibility and in terms of analysis. For example, if a function is
known to be idempotent, then a call to a function which has itself as its argument, and which
is known to have ...
Examples - Department of Computer and Information Science
... Top-Down Programming, also called functional
decomposition, uses functions to hide details of an
algorithm inside the function.
In the prior example, main called
calculate_triangular_number without regards to how the
function is implemented. You can write a call to
calculate_triangular_number withou ...
Programming Lecture 1 notes
... Python, as a programming language, is a particular way of expressing these commands. A Python
program can be viewed as a series of statements, which the computer executes in a sequential order.
That is, a program consists of a list of instructions, or things for the computer to do, and the computer
Elements of Programming Languages Overview Advanced
... How do the “paradigms” actually fit together?
Some features, such as case classes, are more obviously
“object-oriented” versions of “functional” constructs
Until now, we have pretended pairs, λ-abstractions, etc.
are primitives in Scala
They aren’t; and they need to be implemented in a way
Combining Events And Threads For Scalable
... Such massively-concurrent programs are difficult to implement, especially when other requirements, such as high performance and
strong security, must also be met.
Events vs. threads: Two implementation strategies for building
such inherently concurrent systems have been successful. Both the
A Short Cut to Deforestation
... A function which consumes a list in a uniform fashion can
always be expressed by replacing the conses in the list with
a given function , and replacing the nil at the end of the
list by a given value z . This operation is encapsulated by
the higher-order function foldr, which can be informally
Program revision 2
... • An array is an ordered collection, or numbered list, of
values. All of the values in an array must be of the same
type. The type of the array is the type of the values it
holds, followed by the characters . An index is used
to refer to individual values in the array. If we have N
values, we thin ...
Continuations in Scheme
... • Lisp introduced (in the 70’s) catch and throw to
give a non-local return capability
• It was a very useful generalization of return
• (throw ) causes a return from the
nearest matching (catch ) found on stack
(defun foo-outer () (catch (foo-inner)))
(defun foo-inner () … (if x (throw t)) ...
Practical Type Inference Based on Success Typings
... and relatively uneventful activity, at least initially. The occasional
frustrations of having to convince the type system that one really
knows what she is doing are avoided. Also, since type declarations and annotations need not be typed (in), program development
can progress more rapidly. Unfortun ...
Monad (functional programming)
In functional programming, a monad is a structure that represents computations defined as sequences of steps: a type with a monad structure defines what it means to chain operations, or nest functions of that type together. This allows the programmer to build pipelines that process data in steps, in which each action is decorated with additional processing rules provided by the monad. As such, monads have been described as ""programmable semicolons""; a semicolon is the operator used to chain together individual statements in many imperative programming languages, thus the expression implies that extra code will be executed between the statements in the pipeline. Monads have also been explained with a physical metaphor as assembly lines, where a conveyor belt transports data between functional units that transform it one step at a time. They can also be seen as a functional design pattern to build generic types.Purely functional programs can use monads to structure procedures that include sequenced operations like those found in structured programming. Many common programming concepts can be described in terms of a monad structure, including side effects such as input/output, variable assignment, exception handling, parsing, nondeterminism, concurrency, and continuations. This allows these concepts to be defined in a purely functional manner, without major extensions to the language's semantics. Languages like Haskell provide monads in the standard core, allowing programmers to reuse large parts of their formal definition and apply in many different libraries the same interfaces for combining functions.Formally, a monad consists of a type constructor M and two operations, bind and return (where return is often also called unit): The return operation takes a value from a plain type and puts it into a monadic container using the constructor, creating a monadic value. The bind operation takes as its arguments a monadic value and a function from a plain type to a monadic value, and returns a new monadic value.The operations must fulfill several properties to allow the correct composition of monadic functions (i.e. functions that use values from the monad as their arguments or return value). Because a monad can insert additional operations around a program's domain logic, monads can be considered a sort of aspect-oriented programming. The domain logic can be defined by the application programmer in the pipeline, while required aside bookkeeping operations can be handled by a pre-defined monad built in advance.The name and concept comes from category theory, where monads are one particular kind of functor, a mapping between categories; although the term monad in functional programming contexts is usually used with a meaning corresponding to that of the term strong monad in category theory.