doc-src/IsarImplementation/Thy/unused.thy
author wenzelm
Tue Aug 29 18:49:33 2006 +0200 (2006-08-29 ago)
changeset 20429 116255c9209b
parent 18537 2681f9e34390
child 20460 351c63bb2704
permissions -rw-r--r--
more on contexts;
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text {*
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  In practice, super-contexts emerge either by merging existing ones,
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  or by adding explicit declarations.  For example, new theories are
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  usually derived by importing existing theories from the library
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  @{text "\<Theta> = \<Theta>\<^sub>1 + \<dots> + \<Theta>\<^isub>n"}, or 
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  The Isar toplevel works differently for interactive developments
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  vs.\ batch processing of theory sources.  For example, diagnostic
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  commands produce a warning batch mode, because they are considered
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  alien to the final theory document being produced eventually.
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  Moreover, full @{text undo} with intermediate checkpoints to protect
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  against destroying theories accidentally are limited to interactive
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  mode.  In batch mode there is only a single strictly linear stream
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  of potentially desctructive theory transformations.
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  \item @{ML Toplevel.empty} is an empty transition; the Isar command
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  dispatcher internally applies @{ML Toplevel.name} (for the command)
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  name and @{ML Toplevel.position} for the source position.
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*}
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