List's terminology and Parentheses in Perl

You have cited perldocs, unfortunately without linking to the references.

List Terminology

The term "list value" was confusing me, in such cases I recommend looking into perlglossary#LIST ff.

NB: Perlglossary is from an appendix from the Camel (IIRC), while the perldocs were written by different authors.

• LIST

  A syntactic construct representing a comma- separated list of expressions, evaluated to produce a list value. Each expression in a LIST is evaluated in list context and interpolated into the list value.

• list

  An ordered set of scalar values.

• list context

  The situation in which an expression is expected by its surroundings (the code calling it) to return a list of values rather than a single value. Functions that want a LIST of arguments tell those arguments that they should produce a list value. See also context.

• list operator

  An operator that does something with a list of values, such as join or grep. Usually used for named built-in operators (such as print, unlink, and system) that do not require parentheses around their argument list.

• list value

  An unnamed list of temporary scalar values that may be passed around within a program from any list-generating function to any function or construct that provides a list context.

Parentheses

I think one source of confusion (besides @arrays) is the syntactic meaning of parentheses ...(...)... in different constructs.

• ()

  is an empty list

• bareword(...)

  expects a LIST of arguments to a sub bareword °

• (...)[subscript/slice]

  picks elements from a list

• (...) =

  is a list assignment enforcing list context on the RHS updated

... those constructs impose a list context inside

But ...

• "naked" (...) doesn't

  those parens are just for precedence

... neither do they impose their own context nor do they create a "list value".

Examples (updated)

please see Examples for "LIST", "list context", "list value", "list assigment", "list operator"

°) well modulo sub-prototype