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[REBOL] Re: why doesn't this work?

From: jkinraid:clear at: 15-Mar-2001 15:50

Hi Jeff,
> write %params.txt {param1: false} > params: make object! to-block read %params.txt > > returns: ** Script Error: false is not defined in this > context. > ** Where: param1: false > > this does work: > params: make object! [param1: false] > > -- as you'd expect > > and this works too: > > write %params.txt {param1: "text"} > params: make object! to-block read %params.txt > > And that's what's baffling me. > > I'd like to store parameters in a file outside of my > code. I'd like to use an object inside the code to > hold the parameters. If I create the object inside > the code - then read the parameter file stored on disk > and over-write any values in the default parameter > object, it allows the user to overwrite only some > parameters. > > So - why is a boolean value not ok in this context? > Any clues anyone?
When you do a to-block on a string, the resulting block isn't bound to any context.
>> do to-block "{abcd}"
== "abcd"
>> do to-block "true"
** Script Error: true is not defined in this context ** Near: true A string doesn't need to be bound to a context, so it works fine. However, a word needs a context, and there isn't one. Let's make one. another-context: make object! [true: "not false"] blk: to-block "true" do bind blk in another-context 'true == "not false" ; blk is bound to a context where the value of true is the string ; "not false"
>> do blk
== "not false"
>> :blk
== [true] ; Now change blk to use the global context
>> do bind blk 'true
== true The load function will automatically convert your string into a block, *and* bind it to the global context.
>> do load "true"
== true
>> params: make object! load {param1: false} >> params/param1
== false Julian Kinraid