Egor Urvanov

TLA+

Formal verification · by Leslie Lamport

created · updated

A way to describe how a system behaves step by step so precisely that the description can be checked by a program, the way a blueprint is checked before construction. For example, a blueprint of a money transfer reveals that if a failure hits between the debit and the credit, money vanishes, and this is found before any code is written. The notation resembles mathematical formulas, so the entry step is higher than with Quint. The language was created by Leslie Lamport.

a money-transfer blueprintAnnacharged 100a failurethe link brokeBorisgot nothingno code yet: the error is found in advance● model, people, systems, data  ● agent and harness  ● risk, stop, boundaryTLA+ finds the error on the money-transfer blueprint, before any code is written

Source: Leslie Lamport’s TLA+ page

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