'''interp alias''' ''srcPath srcCmd''

Returns a Tcl list whose elements are the ''targetCmd'' and ''args'' associated with the alias named ''srcCmd'' (all of these are the values specified when the alias was created; it is possible that the actual source command in the slave is different from ''srcCmd'' if it was renamed). 

'''interp alias''' ''srcPath srcCmd'' '''{}'''

Deletes the alias for ''srcCmd'' in the slave interpreter identified by ''srcPath''. ''SrcCmd'' refers to the name under which the alias was created;  if the source command has been renamed, the renamed command will be deleted. 

'''interp alias''' ''srcPath srcCmd targetPath targetCmd ?arg arg ...?''

This command creates an alias between one slave and another (see the '''alias''' slave command below for creating aliases between a slave and its master).  In this command, either of the slave interpreters may be anywhere in the hierarchy of interpreters under the interpreter invoking the command. ''SrcPath'' and ''srcCmd'' identify the source of the alias. ''SrcPath'' is a Tcl list whose elements select a particular interpreter.  For example, "'''a b'''" identifies an interpreter '''b''', which is a slave of interpreter '''a''', which is a slave of the invoking interpreter.  An empty list specifies the interpreter invoking the command. ''srcCmd'' gives the name of a new command, which will be created in the source interpreter. ''TargetPath'' and ''targetCmd'' specify a target interpreter and command, and the ''arg'' arguments, if any, specify additional arguments to ''targetCmd'' which are prepended to any arguments specified in the invocation of ''srcCmd''. ''TargetCmd'' may be undefined at the time of this call, or it may already exist; it is not created by this command. The alias arranges for the given target command to be invoked in the target interpreter whenever the given source command is invoked in the source interpreter.

'''interp aliases''' ''?path?''

This command returns a Tcl list of the names of all the source commands for aliases defined in the interpreter identified by ''path''.

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Very often used to introduce command aliases inside the current interpreter (see [Custom curry]), where the alias target may well be a sequence of words:

 interp alias {} strlen {} string length

The case where source and target have identical signatures is [Tcl]'s [idiom]atic way to write a [command] alias:

    interp alias {} new_name {} existing_command

This can be used with some punctuation to make code shorter and potentially 
more readable as long as the reader knows about the alias(es) in effect.

  interp alias {} @ {} lindex
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See [Transliteration] of how to use an alias, besides its original function, as a kind of global data storage

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''Does anybody else here have the guts to admit to using '''echo''' instead of [puts] as often as possible?''  8-)

''Erm ... nope.''

[RS] doesn't, but if you accept the [puts] API (only one string argument), here goes:
 interp alias {} echo {} puts
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See also:

   * [alias]
   * [interp]
   * [interp aliases]
   * [Introspection on aliases]
   * [proc or interp alias]


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Cleverness due to [dgp] (and others):

  interp alias {} err {} return -code error -level 0

More generally, [curry]ing in other languages has these analogues, 
as mentioned above.

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[Tcl syntax help] -
[Category Command] -
[Category Introspection]