Language Syntax Comparison

Language Syntax Comparison



Template
        C               //code
        C++             
        Java            
        Python          
        JavaScript      
        PHP             



Skeleton Program
        C                       int main(int argc, char *argv[]) {  }

        C++                     using namespace std;
                                int main(int argc, char *argv[]) {  }

        Java                    public class Filename {
                                    public static void main(String[] args) {  }
                                }

        Python (in *nix)        #!/usr/bin/python

        JavaScript(in HTML)     <script>
                                </script>

        PHP                     <?php
                                ?>


Comments
        C               // comment      or      /* multi-line comment */
        C++             // comment      or      /* multi-line comment */
        Java            // comment      or      /* multi-line comment */
        Python          # comment       or      ''' docstring, multi-line comment'''
        JavaScript      // comment      or      /* multi-line comment */
        PHP             


Importing Libraries
        C               #include <library.h>
        C++             #include <library>
        Java            import java.library.section
        Python          import library              or          from library import section
        JavaScript      
        PHP             


Command Line Arguments

    How CL Arguments are specified
        C               number of args:     argc
                        values of args:     *argv[]

        C++             number of args:     argc
                        values of args:     *argv[]
        
        Java            number of args:     args.length
                        values of args:     args[]
        
        Python          library to use:     import sys
                        number of args:     len(sys.argv)
                        values of args:     sys.argv[]
                        assign args:        script, arg1, arg2 = argv
        
        JavaScript      
        PHP             

    Put command line arguments in an int array
        C               

        C++             string theArgs[argc];
                        for (i=0; i<argc; i++)
                            theArgs[i] = atoi(argv[i]);

        Java            
        Python          
        JavaScript      
        PHP             


I/O

    Print to screen
        C               printf("", vars);       or      puts("");
        C++             cout << " ";
        Java            System.out.println("");
        Python          print ""
        JavaScript      document.write("");
        PHP             


    Get input from keyboard
        C               
        C++             cin >> input;
        Java            
        Python          raw_input("prompt:")
        JavaScript      
        PHP             


File I/O



Strings and Arrays

    Library to use for Strings:
        C               #include <string.h>
        C++             #include <string>

    Initialize empty Array
        C               datatype array[size];
        C++             datatype array[size];
        Java            datatype[] array = new datatype[size];
        Python          array = []
        JavaScript      
        PHP             

    Get Value at Array Index
        C               array[index]
        C++             array[index]
        Java            array[index]
        Python          array[index]
        JavaScript      array[index]
        PHP             

    Get Character at String Index
        C               str[index]
        C++             str[index]
        Java            str.charAt(index)
        Python          str[index]
        JavaScript      
        PHP             

    Length of an Array
        C               (sizeof(array)/sizeof(*a))
        C++             (sizeof(array)/sizeof(*a))
        Java            array.length
        Python          len(array)
        JavaScript      
        PHP             

    Length of a String
        C               strlen(str)
        C++             str.length()
        Java            str.length
        Python          len(str)
        JavaScript      
        PHP             


Text Processing

    Reverse a String
        C
        C++
        Java
        Python          reversedStr = str[::-1]
        Javascript
        PHP



Functions

    Function Prototypes
        C               returnType funcName(type params, ...);
        C++             returnType funcName(type params, ...);
        Java            N/A
        Python          N/A - must put definition above use
        JavaScript      N/A
        PHP             

    Function Definitions
        C               returnType funcName(type params, ...) {  }
        C++             returnType funcName(type params, ...) {  }
        Java            public static returnType funcName(type params, ...) {  }
        Python          def funcName(params, ...):        - code indented
        JavaScript      function funcName(params, ...) {  }
        PHP             



Class and Objects

    Declaring a Class
        C               N/A

        C++             class ClassName {  }
        
        Java            public class ClassName {  }
        
        Python          class ClassName:
                            code indented
        
        JavaScript      function ObjectName(constructorParams, ...) {  }
        
        PHP