Racket and Shell Commands Vocabulary

Flashcards covering essential vocabulary, list procedures, predicates, control flow structures, higher-order functions, and shell commands from the lecture notes.

first

A function that returns the first item of a list.

rest

A function that returns everything but the first item of a list.

empty?

A predicate that checks if a list is empty.

cons

A function that adds one item to the front of a list.

append

A function that joins two lists together, requiring a list on both sides.

car

The old name for first.

cdr

The old name for rest.

flonum?

A predicate that checks if a value is a floating-point number, which must be checked before integer type checks because (integer? 1.0) returns #t.

quotient

A math function that computes whole-number division.

remainder

A math function that returns the remainder of division; pairs with quotient for base conversion.

apply

A function that spreads a list out as separate arguments for a function that expects them.

cond

A control flow expression that tests clauses top to bottom in order.

let

A control flow structure used to name intermediate results and avoid repeating recursive calls.

lambda

A construct that makes an unnamed function on the spot.

map

A higher-order function that transforms every item in a list using a function.

filter

A higher-order function that keeps only the items in a list that pass a test predicate.

assq

A lookup table search function that uses eq? to compare keys.

assv

A lookup table search function that uses eqv? to compare keys, making it safe for numbers.

assoc

A lookup table search function that uses equal? to compare keys, which works on lists and strings.

remove-duplicates

A function that removes duplicate values from a list.

sort

A function that sorts a list based on a comparison function such as < or symbol<?.

mv

A shell command used to rename or move a file.

cd

A shell command used to change the current directory.

ls -l

A shell command used to list files with details.

touch

A shell command used to create an empty file.