What does car mean in Lisp?
In computer programming, CAR ( car ) /kɑːr/ ( listen) and CDR ( cdr ) (/ˈkʌdər/ ( listen) or /ˈkʊdər/ ( listen)) are primitive operations on cons cells (or “non-atomic S-expressions”) introduced in the Lisp programming language.
Why is it called car and cdr?
car is an acronym from the phrase Contents of the Address part of the Register; and cdr is an acronym from the phrase Contents of the Decrement part of the Register. These phrases refer to specific pieces of hardware on the very early computer on which the Lisp language was developed.
What does cons mean in Lisp?
In computer programming, cons (/ˈkɒnz/ or /ˈkɒns/) is a fundamental function in most dialects of the Lisp programming language. cons constructs memory objects which hold two values or pointers to values. These objects are referred to as (cons) cells, conses, non-atomic s-expressions (“NATSes”), or (cons) pairs.
What does cons mean in scheme?
The primitive procedure cons means “construct.” Cons takes two arguments and returns a list constructed from those two arguments. In this capacity, it provides a means of combination for the Scheme programming language. Note In programming languages, a constructor creates a new object, such as a list object.
What is car return Lisp?
Like car , cdr does not remove any elements from the list—it just returns a report of what the second and subsequent elements are. Incidentally, in the example, the list of flowers is quoted. If it were not, the Lisp interpreter would try to evaluate the list by calling rose as a function.
What is Lisp full form?
LISP, an acronym for list processing, is a programming language that was designed for easy manipulation of data strings. Developed in 1959 by John McCarthy, it is a commonly used language for artificial intelligence (AI) programming. It is one of the oldest programming languages still in relatively wide use.
What does car stand for in racket?
car == return the first element in a pair. > cdr == return the second element in a pair. > >
What CDR means?
Call Detail Record
Call Detail Record (CDR) is the detailed record of all the telephonic calls that pass through a telephone exchange or any other telecommunications equipment. Call Detail records are maintained by telephone exchanges emitting information in the form of tickets, with respect to individual customers/users.
What does pro and cons stand for?
pros and cons. Arguments or considerations for and against something, as in We’d best weigh all the pros and cons before we decide to add a new wing to the library. This idiom is taken from the Latin pro for “for” and con for “against.” [ Late 1500s]
Does Lisp use linked list?
Present day’s Common LISP provides other data structures like, vector, hash table, classes or structures. Lists are single linked lists. In LISP, lists are constructed as a chain of a simple record structure named cons linked together.
What is member in scheme?
Simple functions Notice that each equality only involves constants the parameters have been substituted for by the values bound to them. member is a function that treats a list as a set. It returns true if the item is found in the list, and false otherwise.
What does ++ mean in Haskell?
The ++ operator is the list concatenation operator which takes two lists as operands and “combine” them into a single list.