MACROMEDIA COLDFUSION MX 61-DEVELOPING COLDFUSION MX, Develop Manual

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130 Chapter 6: Extending ColdFusion Pages with CFML Scripting
The following rules apply to statements:
•
You must put a semicolon at the end of a statement.
•
Line breaks are ignored. A single statement can cross multiple lines.
•
White space is ignored. For example, it does not matter whether you precede a semicolon with
a space character.
•
Use curly braces to group multiple statements together into one logical statement unit.
•
Unless otherwise indicated, you can use any ColdFusion expression in the body of a statement.
Note: This chapter documents all statements except
function
,
var
, and
return
. For information on
these statements, see Chapter 10, “Defining functions in CFScript,” on page 198 .
Statement blocks
Curly brace characters ({ and }) group multiple CFScript statements together so that they are
treated as a single unit or statement. This enables you to create code blocks in conditional
statements, such as the following:
if(score GT 0) {
result = "positive";
Positives = Pos 1;
}
In this example, both assignment statements are executed if the score is greater than 0. If they
were not in the code block, only the first line would execute.
You do not have to put brace characters on their own lines in the code. For example, you could
put the open brace in the preceding example on the same line as the
if
statement, and some
programmers use this style. However, putting at least the ending brace on its own line makes it
easier to read the code and separate out code blocks.
Comments
CFScript has two forms of comments: single line and multiline.
A single line comment begins with two forward slashes (//) and ends at the line end; for example:
//This is a single-line comment.
//This is a second single-line comment.
A multiline comment starts with a /* marker and continues until it reaches a */ marker; for
example:
/*This is a multiline comment.
You do not need to start each line with a comment indicator.
This is the last line in the comment. */
The following rules apply to comments:
•
Comments do not have to start at the beginning of a line. They can follow active code on a
line. For example, the following line is valid:
MyVariable = 12; // Set MyVariable to the default value.
switch-case break return (in custom functions only)
for continue