DOCSLIB.ORG

Value Returning Functions 1 Value Returning Functions the C++ Library Provides a Number of Useful Predefined Functions

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Value Returning Functions 1 Value Returning Functions the C++ Library Provides a Number of Useful Predefined Functions Value Returning Functions 1 Value Returning Functions The C++ library provides a number of useful predefined functions. However, in many situations we may have to write our own functions. Writing a function involves two things: a declaration and a definition. Consider the following example program. The program defines and uses a function rectangleArea which computes the area of a rectangle. #include <iostream> using namespace std; int rectangleArea(int, int); // function declaration // returns area of rectangle given length and width int main() { int length, width, area; cout << "Enter numbers for length and width:"; cin >> length >> width; if ( length > 0 && width > 0 ) { area = rectangleArea(length, width); // function call cout << "Area of a rectangle with "; cout << "length = " << length << " and width = " << width; cout << " is " << area; } else cout << "One or both of your inputs is not positive"; return 0; } // end of main // function definition int rectangleArea(int len, int wid) // function header { return (len * wid); // function body } // end of function rectangleArea Value Returning Functions 2 Declaration of functions • A function declaration (also referred to as function prototype) is placed in the declaration section, before the main function. • By this declaration, the compiler knows that rectangleArea is a function and the function has to be supplied with two arguments and it will return a value of type int. Moreover, the first argument is of type int and the second arguments is of type int. The general form for the function declaration has exactly four components as shown below. return_value_type function_name (list of parameter types); • The first component of the function declaration specifies what type of value the function returns. In our example case, the function returns a value of type int. • The second component specifies the function name. In our example case, the function name is rectangleArea. Note that the same rules for creating identifiers (variable names), discussed before, also apply for function names. • The third component specifies how many, and what type of arguments that the function takes. In our example case, the function takes two arguments of type int. • The fourth component is the semicolon ; . Note that the parameter list in a function declaration can be specified either as int rectangleArea(int, int); or int rectangleArea(int len, int wid); where the identifiers len and wid are simply place holders. Basically, the parameter list specifies how many and what type of arguments that the function is expected to take. Function definition • The function definition is simply the code written for this function, so that it accomplishes the required subtask. • The function definition is very similar to that of the main part of a program. Indeed, the main part of the program is the function definition for the function whose name is main. Value Returning Functions 3 • A function definition consists of a function header followed by a function body. • The function header has the same signature as the function declaration, except that the header does not have a semicolon at the end. Moreover, the function header must always list the parameter names. Note that including the semicolon in the function header will produce a syntax error. • The function body is enclosed within a pair of curly braces. Thus function body is just like the body of the main part of a program. • The execution of a return statement in the function body returns the single value computed by the function to the point in the program where the function call was made. • A return statement consists of the keyword return followed by an expression. The function rectangleArea in our program has the following statement. return (len * wid); When this return statement is executed, the value of the expression len * wid is returned to the point from where the function was invoked (that is, the place at which the call originated). • The parentheses is not necessary. We can also write the return statement as follows. return len * wid; • The function body can have any number of executable statements. For example, we could write the rectangleArea function as follows. Value Returning Functions 4 int rectangleArea(int len, int wid) { int area; area = len * wid; return area; } Function parameters - arguments • Parameters (also called formal parameters) are variables that belong to the function and appear in the function header. In the rectangleArea function, len and wid are variables. • Arguments appear in the function call. In the statement area = rectangleArea(length, width); the variables length and width are called the arguments of the function call. • A function call supplies the arguments to the function. We can think of the arguments as the input data to the function. • When a function call is made, the formal parameters of the function receive the arguments supplied by the calling statement. • The arguments in the function call and the formal parameters in the function header are matched, one to one, in order from left to right. That is, the first parameter is assigned the value of the first argument, the second parameter is assigned the value of the second argument, and so on. In our example program, consider the function call. Value Returning Functions 5 A function call leads to the following sequence of actions: 1. The function call invokes the function. (That is transfers control to the function.) In our example case the function rectangleArea. 2. Before the execution begins inside the body of the function, memory (of appropriate size) for each formal parameter is allocated. 3. The argument value is copied into the matched formal parameter (the newly allocated memory). In our example case the variables len and wid would contain the same values that are in length and width respectively. Therefore, the variables len and wid are available for rectangleArea function, as if they were declared (and initialized to appropriate values) inside the function body. Arguments in proper order We know that the formal parameters and arguments are matched by order. • Therefore, when we are writing a call to a function, we must be careful to supply the arguments in the same order as the parameters with which they will be paired. For example suppose that we write a function that takes two double values, divides the first value by the second, and returns the result as shown below. // divides the first parameter by the second and returns the result double divide(double numer, double denom) { return ( numer / denom ); } Now, suppose that we have two variables, say x = 4.0 and y = 2.0 in the calling program, and some z is supposed to get the value x / y. Then consider the following function calls. z = divide(x, y); // This call is correct: z = x / y z = divide(y, x); // This call is incorrect: z = y / x • The above example illustrates that if we confuse the order of the arguments in a function call, the program will not do what we want it to do. Local variables In a function we can declare variables and constants in the body of the function. As discussed before, the formal parameters in the function header are also variables that belong exclusively to the function. Value Returning Functions 6 For example, the variables len, wid and area are the variables that belong exclusively to the function rectangleArea shown below. int rectangleArea(int len, int wid) { int area; area = len * wid; return area; } All these variables and constants are said to be local to the function because they are accessible only within the function. The memory for these local variables is created when the function call is executed and they are deleted upon completion of the function execution. The name of a formal parameter could be the same as or different from the name of the matched argument. It is important to know that the arguments are matched in order to the formal parameters; not by similarity of names. Therefore, even if an argument and its matched parameter have the same name, they are two different variables, each with its own memory cell. The scope of variables We know that when a variable is declared, a particular memory cell (of appropriate size) is created in the memory. The scope (or visibility) of a variable is the block of a program in which the variable can be accessed. That is, the statements of the program block can use that variable to refer to that particular memory cell. The scope of local variables (which includes formal parameters) of a function is limited to the body of the function. Argument passing by value We have been referring to the parameters in the function header as formal parameters. • Parameters in a function header are formal in the sense that any name can be used for them without changing the meaning of the function. In mathematics, we have the same situation; for example, f(x) = x2 and f(y) = y2 define the same function. • Formal parameters are local to a function. Value Returning Functions 7 • When a function call is made, a copy of the value of the actual argument is passed to the corresponding formal parameter. That is, the arguments are passed by value. • With pass by value, a function can work only on copies of arguments, not on the actual arguments themselves. Thus, the actual arguments have the same value before and after the function call. For example, consider the following program: #include <iostream> using namespace std; int changeValue(int x); // function declaration // changes x value as x = x+10 and prints the new value of x int main() { int x = 40; cout << "Value of x in main before function call = " << x << endl; int y = changeValue(x); cout << "Value of x in main after return from function = " << x << endl; return 0; } // end function main // function definition int changeValue(int x) // function header { x += 10; cout << "Value of x after x = x+10 in the function = " << x << endl; return x; } Output of the above program.
Load more

Recommended publications
  • Chapter 4 Programming in Perl
    Chapter 4 Programming in Perl 4.1 More on built-in functions in Perl There are many built-in functions in Perl, and even more are available as modules (see section 4.4) that can be downloaded from various Internet places. Some built-in functions have already been used in chapter 3.1 and some of these and some others will be described in more detail here. 4.1.1 split and join (+ qw, x operator, \here docs", .=) 1 #!/usr/bin/perl 2 3 $sequence = ">|SP:Q62671|RATTUS NORVEGICUS|"; 4 5 @parts = split '\|', $sequence; 6 for ( $i = 0; $i < @parts; $i++ ) { 7 print "Substring $i: $parts[$i]\n"; 8 } • split is used to split a string into an array of substrings. The program above will write out Substring 0: > Substring 1: SP:Q62671 Substring 2: RATTUS NORVEGICUS • The first argument of split specifies a regular expression, while the second is the string to be split. • The string is scanned for occurrences of the regexp which are taken to be the boundaries between the sub-strings. 57 58 CHAPTER 4. PROGRAMMING IN PERL • The parts of the string which are matched with the regexp are not included in the substrings. • Also empty substrings are extracted. Note, however that trailing empty strings are removed by default. • Note that the | character needs to be escaped in the example above, since it is a special character in a regexp. • split returns an array and since an array can be assigned to a list we can write: splitfasta.ply 1 #!/usr/bin/perl 2 3 $sequence=">|SP:Q62671|RATTUS NORVEGICUS|"; 4 5 ($marker, $code, $species) = split '\|', $sequence; 6 ($dummy, $acc) = split ':', $code; 7 print "This FastA sequence comes from the species $species\n"; 8 print "and has accession number $acc.\n"; splitfasta.ply • It is not uncommon that we want to write out long pieces of text using many print statements.
    [Show full text]
  • 1. Introduction to Structured Programming 2. Functions
    UNIT -3Syllabus: Introduction to structured programming, Functions – basics, user defined functions, inter functions communication, Standard functions, Storage classes- auto, register, static, extern,scope rules, arrays to functions, recursive functions, example C programs. String – Basic concepts, String Input / Output functions, arrays of strings, string handling functions, strings to functions, C programming examples. 1. Introduction to structured programming Software engineering is a discipline that is concerned with the construction of robust and reliable computer programs. Just as civil engineers use tried and tested methods for the construction of buildings, software engineers use accepted methods for analyzing a problem to be solved, a blueprint or plan for the design of the solution and a construction method that minimizes the risk of error. The structured programming approach to program design was based on the following method. i. To solve a large problem, break the problem into several pieces and work on each piece separately. ii. To solve each piece, treat it as a new problem that can itself be broken down into smaller problems; iii. Repeat the process with each new piece until each can be solved directly, without further decomposition. 2. Functions - Basics In programming, a function is a segment that groups code to perform a specific task. A C program has at least one function main().Without main() function, there is technically no C program. Types of C functions There are two types of functions in C programming: 1. Library functions 2. User defined functions 1 Library functions Library functions are the in-built function in C programming system. For example: main() - The execution of every C program starts form this main() function.
    [Show full text]
  • Eloquent Javascript © 2011 by Marijn Haverbeke Here, Square Is the Name of the Function
    2 FUNCTIONS We have already used several functions in the previous chapter—things such as alert and print—to order the machine to perform a specific operation. In this chap- ter, we will start creating our own functions, making it possible to extend the vocabulary that we have avail- able. In a way, this resembles defining our own words inside a story we are writing to increase our expressive- ness. Although such a thing is considered rather bad style in prose, in programming it is indispensable. The Anatomy of a Function Definition In its most basic form, a function definition looks like this: function square(x) { return x * x; } square(12); ! 144 Eloquent JavaScript © 2011 by Marijn Haverbeke Here, square is the name of the function. x is the name of its (first and only) argument. return x * x; is the body of the function. The keyword function is always used when creating a new function. When it is followed by a variable name, the new function will be stored under this name. After the name comes a list of argument names and finally the body of the function. Unlike those around the body of while loops or if state- ments, the braces around a function body are obligatory. The keyword return, followed by an expression, is used to determine the value the function returns. When control comes across a return statement, it immediately jumps out of the current function and gives the returned value to the code that called the function. A return statement without an expres- sion after it will cause the function to return undefined.
    [Show full text]
  • Control Flow, Functions
    UNIT III CONTROL FLOW, FUNCTIONS 9 Conditionals: Boolean values and operators, conditional (if), alternative (if-else), chained conditional (if-elif-else); Iteration: state, while, for, break, continue, pass; Fruitful functions: return values, parameters, local and global scope, function composition, recursion; Strings: string slices, immutability, string functions and methods, string module; Lists as arrays. Illustrative programs: square root, gcd, exponentiation, sum an array of numbers, linear search, binary search. UNIT 3 Conditionals: Boolean values: Boolean values are the two constant objects False and True. They are used to represent truth values (although other values can also be considered false or true). In numeric contexts (for example when used as the argument to an arithmetic operator), they behave like the integers 0 and 1, respectively. A string in Python can be tested for truth value. The return type will be in Boolean value (True or False) To see what the return value (True or False) will be, simply print it out. str="Hello World" print str.isalnum() #False #check if all char are numbers print str.isalpha() #False #check if all char in the string are alphabetic print str.isdigit() #False #test if string contains digits print str.istitle() #True #test if string contains title words print str.isupper() #False #test if string contains upper case print str.islower() #False #test if string contains lower case print str.isspace() #False #test if string contains spaces print str.endswith('d') #True #test if string endswith a d print str.startswith('H') #True #test if string startswith H The if statement Conditional statements give us this ability to check the conditions.
    [Show full text]
  • The Return Statement a More Complex Example
    We Write Programs to Do Things Anatomy of a Function Definition • Functions are the key doers name parameters Function Call Function Definition def plus(n): Function Header """Returns the number n+1 Docstring • Command to do the function • Defines what function does Specification >>> plus(23) Function def plus(n): Parameter n: number to add to 24 Header return n+1 Function Precondition: n is a number""" Body >>> (indented) x = n+1 Statements to execute when called return x • Parameter: variable that is listed within the parentheses of a method header. The vertical line Use vertical lines when you write Python indicates indentation on exams so we can see indentation • Argument: a value to assign to the method parameter when it is called The return Statement A More Complex Example • Format: return <expression> Function Definition Function Call § Used to evaluate function call (as an expression) def foo(a,b): >>> x = 2 § Also stops executing the function! x ? """Return something >>> foo(3,4) § Any statements after a return are ignored Param a: number • Example: temperature converter function What is in the box? Param b: number""" def to_centigrade(x): x = a A: 2 """Returns: x converted to centigrade""" B: 3 y = b C: 16 return 5*(x-32)/9.0 return x*y+y D: Nothing! E: I do not know Understanding How Functions Work Text (Section 3.10) vs. Class • Function Frame: Representation of function call Textbook This Class • A conceptual model of Python to_centigrade 1 Draw parameters • Number of statement in the as variables function body to execute next to_centigrade x –> 50.0 (named boxes) • Starts with 1 x 50.0 function name instruction counter parameters Definition: Call: to_centigrade(50.0) local variables (later in lecture) def to_centigrade(x): return 5*(x-32)/9.0 1 Example: to_centigrade(50.0) Example: to_centigrade(50.0) 1.
    [Show full text]
  • 3. Fortran Program Interfaces
    Chapter 3 3. Fortran Program Interfaces Sometimes it is necessary to create a program that combines modules written in Fortran and another language. For example, • In a Fortran program, you need access to a facility that is only available as a C function, such as a member of a graphics library. • In a program in another language, you need access to a computation that has been implemented as a Fortran subprogram, for example one of the many well-tested, efficient routines in the BLAS library. Tip: Fortran subroutines and functions that give access to the IRIX system functions and other IRIX facilities already exist, and are documented in Chapter 4 of this manual. This chapter focuses on the interface between Fortran and the most common other language, C. However other language can be called, for example C++. Note: You should be aware that all compilers for a given version of IRIX use identical standard conventions for passing parameters in generated code. These conventions are documented at the machine instruction level in the MIPSpro Assembly Language Programmer's Guide, which also details the differences in the conventions used in different releases. How Fortran Treats Subprogram Names The Fortran compiler normally changes the names of subprograms and named common blocks while it translates the source file. When these names appear in the object file for reference by other modules, they are normally changed in two ways: • converted to all lowercase letters • extended with a final underscore ( _ ) character 27 Chapter 3: Fortran Program Interfaces Normally the following declarations SUBROUTINE MATRIX function MixedCase() COMMON /CBLK/a,b,c produce the identifiersmatrix_, mixedcase_, and cblk_ (all lowercase with appended underscore) in the generated object file.
    [Show full text]
  • Subroutines – Get Efficient
    Subroutines – get efficient So far: The code we have looked at so far has been sequential: Subroutines – getting efficient with Perl do this; do that; now do something; finish; Problem Bela Tiwari You need something to be done over and over, perhaps slightly [email protected] differently depending on the context Solution Environmental Genomics Thematic Programme Put the code in a subroutine and call the subroutine whenever needed. Data Centre http://envgen.nox.ac.uk Syntax: There are a number of correct ways you can define and use Subroutines – get efficient subroutines. One is: A subroutine is a named block of code that can be executed as many times #!/usr/bin/perl as you wish. some code here; some more here; An artificial example: lalala(); #declare and call the subroutine Instead of: a bit more code here; print “Hello everyone!”; exit(); #explicitly exit the program ############ You could use: sub lalala { #define the subroutine sub hello_sub { print "Hello everyone!\n“; } #subroutine definition code to define what lalala does; #code defining the functionality of lalala more defining lalala; &hello_sub; #call the subroutine return(); #end of subroutine – return to the program } Syntax: Outline review of previous slide: Subroutines – get efficient Syntax: #!/usr/bin/perl Permutations on the theme: lalala(); #call the subroutine Defining the whole subroutine within the script when it is first needed: sub hello_sub {print “Hello everyone\n”;} ########### sub lalala { #define the subroutine The use of an ampersand to call the subroutine: &hello_sub; return(); #end of subroutine – return to the program } Note: There are subtle differences in the syntax allowed and required by Perl depending on how you declare/define/call your subroutines.
    [Show full text]
  • Explain Function Declaration Prototype and Definition
    Explain Function Declaration Prototype And Definition ligatedreprobated,Sidearm feminizes and but road-hoggish Weylin vengefully. phonemic Roderich nose-dived never reckons her acetones. his carat! Unfabled Dubitative Dewey and ill-equippedclangour, his Jerzy stringer See an example of passing control passes to function declaration and definition containing its prototype Once which is declared in definition precedes its definition of declaring a body of. Check out to explain basic elements must be explained below. They gain in this browser for types to carry out into parts of functions return statement of your pdf request that same things within your program? Arguments and definitions are explained below for this causes an operator. What it into two. In definition and declare a great; control is declared in this parameter names as declaring extern are explained in expressions and ms student at runtime error. Classes and definition was tested in a, and never executed but it will be called formal parameters are expanded at later. There are definitions to prototype definition tells the value method of an example are a function based on the warnings have had been declared. Please enter valid prototype definition looks a function definitions affects compilation. In this method is fixed words, but unlike references or rethrow errors or constants stand out its argument is only if more code by subclasses. How do is the variable of the three basic behavior of variable num to explain actual values of yours i desired. Also when a function num_multiplication function and definition example. By value of the definitions are explained in the nested function, the program passes to.
    [Show full text]
  • Subprograms Subroutines Procedures Functions Methods
    Subprograms Subroutines 17/05/2017 Procedures Functions Methods An introduction DFR -- PL Subprograms 1 What is a subprogram? • A “code package” with a name, … • … and possibly parameters … • … and a type (functions) 17/05/2017 Inspired by the idea of a mathematical function BUT mathematical functions have only IN PARAMETERS SUBPROGRAMS may have IN, OUT & IN‐OUT parameters (ADA) DFR -- PL Subprograms Code abstractions – reusable, lead to more abstract design Modules and interfaces 2 Terminology & Ideas • Between different programming languages, the terminology is mixed • E.g. Lisp calls these “procedures” BUT they return a value • E.g. OO calls these “methods” 17/05/2017 • E.g. C calls them functions but allows a void type procedure • Subprograms introduce the concept of scope since they define a new “environment” • The scope of a name is the environment or environments in which the name is visible or accessible DFR -- PL Subprograms • This in turn leads to “name hiding” –when a name in a subroutine hides another object with the same name in an outer environment 3 • local and non‐local environments Parameters • Subprograms may have parameters • FORMAL PARAMETER IDENTIFIER 17/05/2017 • ACTUAL PARAMETER EXPRESSION • Examples 2 literal value 2+2 literal expression DFR -- PL Subprograms The actual parameters aidentifier are the ARGUMENTS to the subprogram f(x) function call a + f(x) * 2 expression 4 Parameters Parameter passing semantics also use mixed terminology! Call-by IN OUT IN-OUT Pass-by 17/05/2017 Value Reference Return DFR -- PL
    [Show full text]
  • DWARF Debugging Information Format
    DWARF Debugging Information Format UNIX International Programming Languages SIG Revision: 1.1.0 (October 6, 1992) Published by: UNIX International Waterview Corporate Center 20 Waterview Boulevard Parsippany, NJ 07054 for further information, contact: Vice President of Marketing Phone: +1 201-263-8400 Fax: +1 201-263-8401 International Offices: UNIX International UNIX International UNIX International UNIX International Asian/Pacific Office Australian Office European Office Pacific Basin Office Shinei Bldg. 1F 22/74 - 76 Monarch St. 25, Avenue de Beaulieu Cintech II Kameido Cremorne, NSW 2090 1160 Brussels 75 Science Park Drive Koto-ku, Tokyo 136 Australia Belgium Singapore Science Park Japan Singapore 0511 Singapore Phone:(81) 3-3636-1122 Phone:(61) 2-953-7838 Phone:(32) 2-672-3700 Phone:(65) 776-0313 Fax: (81) 3-3636-1121 Fax: (61) 2 953-3542 Fax: (32) 2-672-4415 Fax: (65) 776-0421 Copyright 1992 UNIX International, Inc. Permission to use, copy, modify, and distribute this documentation for any purpose and without fee is hereby granted, provided that the above copyright notice appears in all copies and that both that copyright notice and this permission notice appear in supporting documentation, and that the name UNIX International not be used in advertising or publicity pertaining to distribution of the software without specific, written prior permission. UNIX International makes no representations about the suitability of this documentation for any purpose. It is provided "as is" without express or implied warranty. UNIX INTERNATIONAL DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS DOCUMENTATION, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL UNIX INTERNATIONAL BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS DOCUMENTATION.
    [Show full text]
  • CSE 341 Lecture 26
    CSE 341 Lecture 26 OOP, prototypes, and inheritance slides created by Marty Stepp http://www.cs.washington.edu/341/ How to get a "class"? • What if we want to create a class, not just one object? JavaScript, unlike Java, does NOT have classes we could emulate a constructor with a function: // Creates and returns a new Point object. function constructPoint (xValue, yValue) { // bad code return { x: xValue, y: yValue, distanceFromOrigin: function() { return Math.sqrt(this.x * this.x + this.y * this.y; } }; } > var p = constructPoint(4, -3); 2 Problems with pseudo-constructor function constructPoint (xValue, yValue) { // bad code return { x: xValue, y: yValue, distanceFromOrigin: function() { return Math.sqrt(this.x * this.x + this.y * this.y; } }; } ugly doesn't match the " new " syntax we're used to wasteful; stores a separate copy of the distanceFromOrigin method in each Point object 3 Functions as constructors // Constructs and returns a new Point object. function Point (xValue, yValue) { this .x = xValue; this .y = yValue; this .distanceFromOrigin = function() { return Math.sqrt( this .x * this .x + this .y * this .y); }; } > var p = new Point(4, -3); a constructor is just a normal function! called with new like in Java 4 Functions as constructors • in JavaScript, any function can be used as a constructor! by convention, constructors' names begin in uppercase when a function is called w/ new , it implicitly returns this function Point(x, y) { this.x = x; this.y = y; } all global "classes" ( Number , String , etc.) are functions
    [Show full text]
  • PHP: Constructs and Variables Introduction This Document Describes: 1
    PHP: Constructs and Variables Introduction This document describes: 1. the syntax and types of variables, 2. PHP control structures (i.e., conditionals and loops), 3. mixed-mode processing, 4. how to use one script from within another, 5. how to define and use functions, 6. global variables in PHP, 7. special cases for variable types, 8. variable variables, 9. global variables unique to PHP, 10. constants in PHP, 11. arrays (indexed and associative), Brief overview of variables The syntax for PHP variables is similar to C and most other programming languages. There are three primary differences: 1. Variable names must be preceded by a dollar sign ($). 2. Variables do not need to be declared before being used. 3. Variables are dynamically typed, so you do not need to specify the type (e.g., int, float, etc.). Here are the fundamental variable types, which will be covered in more detail later in this document: • Numeric 31 o integer. Integers (±2 ); values outside this range are converted to floating-point. o float. Floating-point numbers. o boolean. true or false; PHP internally resolves these to 1 (one) and 0 (zero) respectively. Also as in C, 0 (zero) is false and anything else is true. • string. String of characters. • array. An array of values, possibly other arrays. Arrays can be indexed or associative (i.e., a hash map). • object. Similar to a class in C++ or Java. (NOTE: Object-oriented PHP programming will not be covered in this course.) • resource. A handle to something that is not PHP data (e.g., image data, database query result).
    [Show full text]