That's how the parser is organized.

you must distinguish between

• Compound-Statements without semicolons because they are part of special syntax
• Builtin Commands/Functions which are part of terms and expressions which can be nested and chained
• Simple-Statements which must be separated by semicolons, and consist of at least one expression.

(Contrived) Examples:

map and eval fall into the function category.

• @x = map { $_ ** 2  } @y ;

  you can see multiple nested terms and functions in the statement

• for ( eval{ some_func() } ) { print }

  for (EXPR) {BLOCK} is a compound statement and eval is single EXPR without(!) semicolon

NB: If you wanted to use a compound statement inside an expression, you would need to put it inside do {BLOCK}

HTH! :)

updates

added links to simple-statements, terms and expressions

PS: It's a bit confusing that Larry's definition of "Term" (leaf of the syntax-tree) is different to the one in mathematics.

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