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Syntax of a Simple Imperative Language Operational semantics Syntax (IntExp)e ::n I x I e+e l e-e l... Here n ranges over the numerals 0,1,2,.... We distinguish between numerals,written n,0,1,2,...,and the natural numbers,written n,0,1,2,....The natural numbers are the normal numbers that we use in everyday life,while the numerals are just syntax for describing these numbers. We write Ln]to denote the meaning of n.We assume that Ln]=n, l0=0,l1J=1,.. The distinction is subtle,but important,because it is one manifestation of the difference between syntax and semantics. Operational Semantics Syntax of a Simple Imperative Language Operational semantics Syntax (IntExp) e ::= n | x | e + e | e − e | . . . Here n ranges over the numerals 0, 1, 2, . . . . We distinguish between numerals, written n, 0, 1, 2, . . . , and the natural numbers, written n, 0, 1, 2, . . . . The natural numbers are the normal numbers that we use in everyday life, while the numerals are just syntax for describing these numbers. We write bnc to denote the meaning of n. We assume that bnc = n, b0c = 0, b1c = 1, . . . . The distinction is subtle, but important, because it is one manifestation of the difference between syntax and semantics. Operational Semantics
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