I stand corrected.

Nuclear style feature then.

'Let me get out of here {Smalltalk snapshot:false andQuit: true}. BOOM'
interpolate

Feels like

STR='sudo reboot'; $(STR)

in bash when one is sudoer.

Phil

On Thu, Sep 28, 2017 at 4:43 PM, Sven Van Caekenberghe <s...@stfx.eu> wrote:

>
>
> > On 28 Sep 2017, at 16:27, p...@highoctane.be wrote:
> >
> > We also have http://norbert.hartl.name/blog/2013/10/03/mustache-
> templates-for-smalltalk/
> >
> > Phil
>
> Yes, Mustache is a cool templating engine, but it is similar to #format:
> not to #interpolate. With true string interpolation, you do not provide a
> context, you just write the expressions inline. Compare the following two:
>
> 'Today is {1} format: { Date today }.
>
> 'Today is { Date today }' interpolate.
>
> > On Thu, Sep 28, 2017 at 4:20 PM, Sven Van Caekenberghe <s...@stfx.eu>
> wrote:
> > Hi,
> >
> > I got into a little office discussion about string interpolation as it
> is done in different programming languages.
> >
> > In Pharo we have String>>#format: which is pretty nice. It works as
> follows:
> >
> > | x y |
> > x := 123.
> > y := #foo.
> > 'x={1} and y={2}' format: { x. y }.
> >
> > It is also possible to use a dictionary with keys, like this:
> >
> > | x y |
> > x := 123.
> > y := #foo.
> > 'x={x} and y={y}' format: { #x->x. #y->y } asDictionary.
> >
> > But this is not true string interpolation as described in [
> https://en.wikipedia.org/wiki/String_interpolation ]. The idea is to
> write the value generating expressions directly inside the strings.
> >
> > Since in Pharo we add features not by extending the syntax but by adding
> messages I wondered if it could be done for string interpolation. The goal
> is to make the following work:
> >
> > | x y |
> > x := 123.
> > y := #foo.
> > 'It seems x equals {x} and y equals {y} while Pi is still {Float pi}'
> interpolate.
> >
> >  => 'It seems x equals 123 and y equals foo while Pi is still
> 3.141592653589793'
> >
> > Here is the implementation I came up with:
> >
> > String>>#interpolate
> >   "Format the receiver by interpolating the evaluation of expressions
> >   in between curly brackets in the context of the sender as in the
> following 3 oneline examples.
> >   'Today is {Date today}' interpolate.
> >   | x | x := 123. 'x equals {x} and pi equals {Float pi}' interpolate.
> >   'In {#strings} you can escape \{ by prefixing it with \\' interpolate."
> >
> >   | senderContext |
> >   senderContext := thisContext sender.
> >   ^ self class new: self size streamContents: [ :out | | stream |
> >       stream := self readStream.
> >       [ stream atEnd ] whileFalse: [ | currentChar |
> >         (currentChar := stream next) == ${
> >           ifTrue: [ | expression result |
> >             expression := stream upTo: $}.
> >             result := Compiler new
> >               evaluate: expression in: senderContext to: nil notifying:
> nil ifFail: [ ^ nil ] logged: false.
> >             out nextPutAll: result asString ]
> >           ifFalse: [
> >             currentChar == $\
> >               ifTrue: [ stream atEnd ifFalse: [ out nextPut: stream next
> ] ]
> >               ifFalse: [ out nextPut: currentChar ] ] ] ]
> >
> > It is a hack that could certainly be improved. And there is of course an
> obvious security problem.
> >
> > Thoughts ?
> >
> > Sven
> >
> >
> >
>
>
>

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