PERL: Statements

Simple Statements, Blocks, Compound Statements

Simple Statements

A simple statement is an expression evaluted for its results. A simple statement may be followed by a modifier (only one).

$rain = "wet"; # simple statment

$storms++; # me too! Notice I end with a ;

#simple statement plus modifier

$I_am = "wet" if $raining;

As you can see, all simple statments must end with a semicolon (;). Here are some other modifiers (not an exclusive list):

STATEMENT if EXPR;

STATEMENT while EXPR;

STATEMENT unless EXPR;

Compound Statements

A BLOCK is when a group of statements are together in a sequence and are surrounded by curly braces ({}). When you use blocks with expressions you can build compound statements such as:

#sample compound statement

if ($UGA_score > $FLA_score) {

$UGA_status = "party town";

$FLA_status = "gator meat";

}

Notice that you have an 'if' statement, followed by an 'expression', then an open curly brace {. The curly brace denotes the start of a block while the ending curly brace denotes the end of the block. The two statements in the middle comprise the body of the block.

Other compound statements (not an exclusive list):

if (EXPR) BLOCK

if (EXPR) BLOCK else BLOCK

if (EXPR) BLOCK elsif BLOCK else BLOCK

LABEL: while (EXPR) BLOCK

LABEL: for (EXPR; EXPR; EXPR) BLOCK

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