TITLE

DRAFT: Synopsis 32: Setting Library - Callable

AUTHORS

Tim Nelson <wayland@wayland.id.au>
Larry Wall <larry@wall.org>

VERSION

Created: 26 Feb 2009

Last Modified: 3 May 2009
Version: 2

The document is a draft.

If you read the HTML version, it is generated from the Pod in the specs repository under https://github.com/perl6/specs/blob/master/S32-setting-library/Callable.pod so edit it there in the git repository if you would like to make changes.

This document documents Code, Block, Signature, Capture, Routine, Sub, Method, Submethod, and Macro.

Roles

Callable

role Callable {...}

The Callable role implies the ability to support postcircumfix:<( )>.

Code

# Base class for all executable objects
role Code {
    method Signature signature() {...}
    method Code      assuming(...) {...}
    method           do() {...} # See L<S12/Introspection>
    method Bool defined {...}
    # XXX What does do() return?  I mean, it's a "method body", but what's that?
}

For Code, the .defined method returns whether a body has been defined. A body consisting only of ..., !!!, or ??? (with optional message arguments) does not count as defined.

To test if a name has been declared, look up the symbol in the appropriate symbol table.

Block

# Executable objects that have lexical scopes
role Block does Code does Callable {
    method next() {...}
    method last() {...}
    method redo() {...}
    method leave() {...}
    method labels() {...}
    method as() {...} # See L<S12/Introspection> and L<S02/Value types>
}

Signature

# Function parameters (left-hand side of a binding)
role Signature {...}

Capture

# Function call arguments (right-hand side of a binding)
role Capture does Positional does Associative {...}

WrapHandle

role WrapHandle {...}

Classes

Routine

class Routine does Block {
     method WrapHandle wrap(Code $code) {...}
     method Routine    unwrap(Wraphandle $original) {...}
     method Str        name() {...}
     method Bool       multi() {...}
}
unwrap

See "Wrapping" in S06.

wrap
method wrap(Code $code) {...}

See "Wrapping" in S06.

Sub

class Sub isa Routine {...}

Method

class Method isa Routine {...}

Submethod

class Submethod isa Routine {...} # XXX or should this be isa Sub

Macro

class Macro isa Routine {...}

Additions

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