Questions tagged [semantics]

Semantics formally describe the meaning of some syntax.

150 questions
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Is natural semantics a total or partial function

I have the following def's Sns : Stm → (State ֒→ State) Sns[S] = s' (if <S,s> -> s') else undefined I'm wondering if ...
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Prooving equations are non derivable in Sigma algebra

Let Σ be the signature made up from the following symbols. e: 0 arguments function (constant symbol) f: 2 arguments function g: 1 argument function Variable set Var is made up from x,y,z Let E be ...
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What is the relation between an algorithm and its implementation at the level of code?

Is there any isomorphism or equivalence relation? What strictly bind these two together?
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What is a “model” of lambda calculus?

I know about the concept of the "model" of a logical proposition in the context of mathematical logic: It is a mathematical structure in which that proposition is true. However, it's not clear to me ...
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The definition of weakest precondition for a non-deterministic language

In the classical IMP language, the definition of weakest precondition is: definition "wp c Q s ≡ ∃t. (c,s) ⇒ t ∧ Q t" This is stating that from state s, after ...
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The Law of Excluded Miracle in the language of guarded commands

The definition of weakest precondition is familiar (let me use Isabelle's syntax here): definition "wp c Q s ≡ ∃t. (c,s) ⇒ t ∧ Q t" the weakest precondition ...
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What does it mean to “strengthen the precondition and weaken the postcondition” in Hoare logic?

Having learned a rough summary of Hoare logic (i.e. learning just the basic concept of Hoare triples and a few of the rules) I kept seeing a statement along these lines: The rule of consquence ...
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Programming Symbols : Instance/Instantiation

Is there a generally accepted symbol for indicating instantiation. That is indicating an object is an instance of a class. My first guess is to use a left arrow with a double or triple line but this ...
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Programming language semantics prototyping tool

Is there any tool for prototyping a programming language semantics and type system and that also allows for some sort of model checking of standard properties, like type soundness? I'm asking this, ...
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Collection of inference rules viewed itself as a judgment

I'm confused about the intended meaning of the following passage from Bob Harper's Practical Foundations for Programming Languages: A collection of rules is considered to define the strongest ...
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Quantifiers in lambda calculus

I'm learning lambda calculus, however I'm quite confused about the quantifiers in lambda calculus. As far as I know, quantifiers such as "∃" are concepts of first order logic (FOL), which are not ...
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What kind of formal semantics can describe HTML and CSS?

What kind of formal semantics can describe HTML and CSS? Are there endeavours to do this. HTML/CSS layouts are espcially complex, so formalization can be of help.
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When would one use equational dynamics?

I'm trying to sort out in my mind the different ways of assigning semantics to a programming language. There are two main methodologies: operational semantics and denotational semantics (I asked a ...
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Is there relation between K-Framework and structural operational semantics?

K-framework strives to give one (instead of two - operational and denotational) semantics for industrial programming languages. The same unification is done by structural operational semantic as well. ...