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In computer science, manifest typing is explicit identification by the software programmer of the ''type'' of each variable being declared. For example: if variable ''X'' is going to store integers then its ''type'' must be declared as integer. The term "manifest typing" is often used with the term latent typing to describe the difference between the static, compile-time type membership of the object and its run-time type identity. In contrast, some programming languages use ''implicit typing'' (a.k.a. type inference) where the type is deduced from context or allow for dynamic typing in which the variable is just declared and may be assigned a value of any type at runtime. ==Examples== Consider the following example written in the C programming language: #include int main(void) Note that the variables ''s'', ''x'', and ''y'' were declared as a character array, floating point number, and an integer, respectively. The type system rejects, at compile-time, such fallacies as trying to add ''s'' and ''x''. In contrast, in Standard ML, the ''types'' are not explicitly declared. Instead, the ''type'' is determined by the type of the assigned expression. let val ''s'' = "Test String" val ''x'' = 0.0 val ''y'' = 0 in ''print'' "Hello World\n" end There are no manifest types in this program, but the compiler still ''infers'' the types string, real and int for them, and would reject the expression s+x as a compile-time error.抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「manifest typing」の詳細全文を読む スポンサード リンク
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