JavaScript: Day 1

Starting Objective

Find resources for learning JavaScript, PHP,  Python.

Action

Looked at Google examples.

Findings

The examples are something I would need to parse to determine the syntax.    Seems like too much work for the benefit.  

Refined Immediate Objective

Select and start a tutorial on JavaScript or PHP that explains the basics of the syntax of a module

• Module declaration
• Module ending 
• Data Declaration: Public, Private, Other???
• If...Then....Else
• Case 
• Looping
• Comments

Longer Term Learning Objectives

• How users interact with modules, e.g.,
• Functions like VBAs MsgBox and MsgInput
• Programmer developed forms
• Controls displayed on documents/spreadsheets/slides
• Triggering from a UI dialogue, e.g., F8 in MS-Office presents a list of macros
• Embedding/including/exploiting User Defined Functions (UDFs) in documents/spreadsheets/slides
• How modules interact with other technical components
• Invoke/Call
• Parameters & Arguments
• Event Models
• Environment variables
• Creating new documents and sub-components, e.g. spreadsheets in a workbook.
• Finding currently open documents
• Opening/saving to folder/file structures and URLs

Action

Selected and started CodeCademy's intro to JavaScript.

Learned

• "//" is the beginning of a comment
• Comment can be at the beginning of a line or at then end
• Once a comment is started, the rest of the line is a comment
• A semi-colon(";") ends a statement
• A semi-colon is not needed at the end of a comment line
• Adding a semi-colon after a comment does not allow a statement after it on the same line
• Basic math operators for addition, subtraction, multiplication and division work as expected ("+","-","/", and "*" respectively
• Remainder function is called "modulo" and the operator is "%".  VBA and Excel us "x mod y" and "mod(x,y)" respectively
• The carat ("^") is not the symbol for exponentiation.

• Variable declaration is done with a "var" statement, e.g. "var myname"
• Assignment of a value to a variable is done with the equals ("=") sign.
• The equivalent of MsgBox is confirm(<string>)
• The equivalent of InputBox is prompt(<string>)
• Default buttons for confirm() are "OK" and "Cancel"
• ".length" is an property, not a method.
• Semi-colon indicates the end of a statement
• Braces ("{}") define code blocks
• If no braces, the code block is one statement
• A code block is a series of statements executed together or not at all.  For example, when there
• Syntax for If ... Else is "if (<condition>)  <true code block> <nl> else <else code block>
• Comparison operators are 
• > Greater than
• < Less than
• <= Less than or equal to
• >= Greater than or equal to
• === Equal to
• !== Not equal to
• JavaScript is case sensitive.  Operators used so far are all lower case.

To Be Learned

• Are their other parameters for confirm(), e.g. Title and Help?
• Are their other button options for confirm()?
• Are their other parameters for prompt(), e.g. Title and Help?
• Are their other button options for prompt()?
• What is a "code block"?
• What is the symbol for exponentiation, "**", as in "2**3 = 8"?