Andreas Lochbihler questions

Andreas Lochbihler answers

• Fixing type variables in locale extensions
• Rewriting with non-equality equivalence-relations using Isabelle simplifier
• Isabelle: Wellsortedness error
• Introducing type abbreviations in Isabelle
• The order of premises
• Isabelle/HOL: What does the THE construct denote?
• Bad theory import in isabelle
• When would you use `presume` in an Isar proof?
• hiding operators to avoid ambiguities in the AST
• How can I fake existential types in Isabelle/HOL?