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[REBOL] simple parse and copy question Re:

From: brett:codeconscious at: 5-Oct-2000 0:36

The "copy" you see in the parse rule is not the same as the copy at the command line. Parse rules are made up from a dialect specific to parse. That is, the code you find in a parse rule is not executed like ordinary script, it is instead interpreted by the parse function. When the parse function encounters the word "copy" in a parse rule it applies its own specific meaning - just like you could if you had a function that processed words in a block. Check out the documentation on parse and you will find that the result of using copy (in parse) is to copy the input stream from the current position for as long as the next match pattern is valid. In contrast, the bits of code you find in a parse rule between a "(" and a ) are normal rebol commands. This allows you to have the power of rebol script from within parse. Another thing you will see in parse rules is a set-word like "here-i-am:". Again, when parse encounters this set-word it applies its own specific meaning, in this case it is to assign the word "here-i-am" to the current location of the input-stream. See the documentation for an example of this use. Hope that explains it. Brett.