TIP #417: Use Explicit Option Names for "file tempfile"
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TIP:	417
Title:	Use Explicit Option Names for "file tempfile"
Version:	$Revision: 1.1 $
Authors:	Christophe Curis <christophe.curis@free.fr>
State:	Draft
Type:	Project
Tcl-Version:	8.7
Vote:	Pending
Created:	Fri Nov 16 00:00:00 UTC 2012
Keywords:	Tcl, future expansion, extensibility
Abstract
This TIP proposes altering the way in which optional arguments are specified to file tempfile (see [210]) to make them easier to understand and extend in the future.
Rationale
The current documentation for file tempfile states that there are two optional arguments using a fixed order. This has some limits:
it is not possible to use the second argument without the first
being an infrequently-used function, having a fixed order implies that a look to the manual page will be obligatory to make sure of the order
this inhibits potential for any future expansion of the command.
Switching to option/value format will make the optional arguments easier to understand.
Proposal
The syntax of the command would be changed to:
file tempfile ?options...?
with supported options:
-namevar variable: Specifies a variable for receiving the file name.
-template template: Defines a template for the file name.
This syntax would allow:
easy extension in the future, as any option name can be added,
ability to use any of the options in any order,
an explicit syntax making the code easier to read and understand.
Reference Implementation
No implementation is available now, but the change is probably not complex; the priority have been placed on raising the subject before the release of the final 8.6 version of Tcl.
Copyright
This document has been placed in the public domain.
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