RE: Declarative programming requires a different mindset

Hi Folks,

It is my understanding that a key characteristic of declarative programming is that statements can be executed in any order, even in parallel. Do you agree?

If yes, then anything which forces sequential processing is, by definition, not declarative. Do you agree?

At the bottom of this message is a variable, namespace-map, which is then used by the second variable. The first variable must be created _before_ the second variable. Thus, a sequential processing is required and therefore it is not declarative.

Wait. That can’t be right.

Then I can’t create building blocks which can be used to create larger building blocks. The first variable is a building block that the second variable builds upon. Surely, assembling building blocks is important in declarative programming?

What is the right way to think about variables that use other variables? Is it bad, from a declarative programming perspective?

<xsl:variable name="namespace-map"

     select="document('')/*//f:namespace-map

         [f:input-document/f:namespace=$ns]" />

<xsl:variable name="use-this-namespace"

      select="$namespace-map/f:output-document/f:namespace" />