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theory Preface
imports Base "HOL-Eisbach.Eisbach_Tools"
begin
text \<open>
\<^emph>\<open>Eisbach\<close> is a collection of tools which form the basis for defining new
proof methods in Isabelle/Isar~@{cite "Wenzel-PhD"}. It can be thought of as
a ``proof method language'', but is more precisely an infrastructure for
defining new proof methods out of existing ones.
The core functionality of Eisbach is provided by the Isar @{command method}
command. Here users may define new methods by combining existing ones with
the usual Isar syntax. These methods can be abstracted over terms, facts and
other methods, as one might expect in any higher-order functional language.
Additional functionality is provided by extending the space of methods and
attributes. The new @{method match} method allows for explicit control-flow,
by taking a match target and a list of pattern-method pairs. By using the
functionality provided by Eisbach, additional support methods can be easily
written. For example, the @{method catch} method, which provides basic
try-catch functionality, only requires a few lines of ML.
Eisbach is meant to allow users to write automation using only Isar syntax.
Traditionally proof methods have been written in Isabelle/ML, which poses a
high barrier-to-entry for many users.
\<^medskip>
This manual is written for users familiar with Isabelle/Isar, but not
necessarily Isabelle/ML. It covers the usage of the @{command method} as
well as the @{method match} method, as well as discussing their integration
with existing Isar concepts such as @{command named_theorems}.
These commands are provided by theory @{theory "HOL-Eisbach.Eisbach"}: it
needs to be imported by all Eisbach applications. Theory theory @{theory
"HOL-Eisbach.Eisbach_Tools"} provides additional proof methods and
attributes that are occasionally useful.
\<close>
end