«if», «else» and «while» are keywords part of "if" statements and "while" statements. Flow control statements don't take semicolons.

while ( COND ) BLOCK
if ( COND ) BLOCK
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The «if» and «while» keywords are also found in statement modifiers. Statements with statement modifiers do take a semicolon.^[1]

EXPR while COND;
EXPR if COND;
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eval and map are "functions" (named operators). Function calls do no take semicolons.

if ( !eval { f() } ) { ... }
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my $x = eval { f() }
   or ...;
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This includes simple statements.^[1] These are statements that consist of nothing but an expression.

EXPR;
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The statement you gave is an example of a simple statement, and so is the «or»-using statement above.

C, C++, C#, JavaScript and Java all work this way.

1. The semicolon can be omitted if it terminates the last statement of a block or file.

Updated to elaborate.