Web Systems and Technologies Prefinal Reviewer

Function

Is a seperate piece of code intended to perform a specific task. It is usually assigned a specific name that is called many times in different program sections

Function Statement

Starts with the function keyword followed by the function name, which follows the same rule as variable names that must relate to the condition to be done

return Statement

Causes the function to end exactly wherever this word is placed in the instruction. It also allows programmers to return a given value from inside the function to the place where it was called

Local Variable

Is only usable inside its corresponding function block

Global Variable

Is usable anywhere in the program.

Parameters

Are names separated by commas, placed inside the parenthesis after the function name, and treated as local variables

Arguments

They refer to the values given when a function is called

Errors

Happens due to misconceptions when solving a problem, improper use and types of the programming language, or the inability to predict user behavior

Syntax

It is term used for grammar in programming language

SyntaxError

Appears when a code is ill-formed. The code cannot be executed as JavaScript cannot understand it

ReferenceError

When the compiler does not know its meaning. This error occurs when the programmer tries to access a function or variable that does not exist

TypeError

This error occurs when a specific value is not of the expected type, such as changing the constant value or checking the length of a variable that is not a string

RangeError

This error is generated when a value is passed to a function outside its acceptable range

Exceptions

Happens when JavaScript detects syntatic or semantic errors, it generates and throws specific objects with information about the encountered error

Run-Time Errors

Appears while the program is running

Exception handling

Also known as error handling, is done to prevent the program from stopping in such a situation

finally Statement

It can be used with or without the catch block and is always executed after the try and catch blocks, no what errors are thrown

Debugging

Is part of troubleshooting in programming

Resume

Resumes the execution of the script typically. The debugger runs the pgoram and “breaks” on user-defined breakpoints

Step Into

Treats the function as a set of instructions intended to be executed separately. It is used when the code needs to be analyzed in detail. The debugger will jump inside the code of the next instruction if it is a function call

Step Over

Is used when the next instruction is a call to a function where the impact is unclear or uninterested. It tr

Step Out

Allows to immediately jump out of a function where the code is paused. This action proceeds until the function returns if the debugger is within the code block