''[CMcC] 8/7/7'' Tcl contains some semantic equivalences such as:

   * '''$ ~~ [[[set]]]'''

Example:
        set abc "123"
        set xyz $abc
or
        set xyz [set abc]


   * '''[[]] ~~ [[[eval]]]'''

Example:

[[replace with example]]


   * '''"" ~~ [[[subst]]]'''

Example:

[[replace with example]]

   * '''global ~~ ::'''

Example:

        set abc $::env(HOME)
or
        global env
        set abc $env(HOME)


Where ''~~'' can be read as ''approximates''

   * '''{} ~~ [[list]]'''

Example:
        set var1 {1 2 3}
        set var1 [list 1 2 3]



Add more if you find them.  The hunt is on.
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''[escargo] 7/7/7 -'' Are you looking for examples how these are '''not''' equivalent?  [CMcC] I changed it to 'approximates.'

For example, I seem to recall that [[[eval]]] does a round of substitution before evaluating
its input.  (Logically, it would seem to be necessary for '''[[]] !~ [[[eval]]]''', otherwise
eval is just taking up space.)

And [subst] takes arguments that allow limitations on the substitutions.

[LV] I think what is being sought are cases where ''there is more than one way to do it'', as the [Perl] community says. This could be cases of Tcl syntactical ''sugar'' (notational shortcut approximates).

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[Category Language]