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Re: printNl question

From: bill-auger
Subject: Re: printNl question
Date: Sun, 18 Apr 2021 19:04:10 -0400

rather than casual explanations of the problem, it is usually
more helpful to show the exact commands and output - for
example, is this what you are seeing?

  $ gst

  st> 'hello' printNl

  st> Transcript show: 'hello' ; cr

the first line is the side-effect of execution (displaying the

the second line is the evaluation of the message chain
(the objects: 'hello' and Transcript) - think of those as the
return result of function evaluation, in other languages - in
both of those cases, the message chain evaluates to the receiver

this is a common idiom for REPLs - it is a little more evident in

  $ irb

  irb(main):001:0> puts 'hello'
  => nil

  irb(main):002:0> 'hello'
  => "hello"

`puts 'hello'` prints the string, then evaluates to nil
`'hello'` has no side-effect - it simply evaluates to itself

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