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diff --git a/doc/manual/definitions.txt b/doc/manual/definitions.txt deleted file mode 100644 index 21954fb78..000000000 --- a/doc/manual/definitions.txt +++ /dev/null @@ -1,49 +0,0 @@ - -Definitions -=========== - -A Nim program specifies a computation that acts on a memory consisting of -components called `locations`:idx:. A variable is basically a name for a -location. Each variable and location is of a certain `type`:idx:. The -variable's type is called `static type`:idx:, the location's type is called -`dynamic type`:idx:. If the static type is not the same as the dynamic type, -it is a super-type or subtype of the dynamic type. - -An `identifier`:idx: is a symbol declared as a name for a variable, type, -procedure, etc. The region of the program over which a declaration applies is -called the `scope`:idx: of the declaration. Scopes can be nested. The meaning -of an identifier is determined by the smallest enclosing scope in which the -identifier is declared unless overloading resolution rules suggest otherwise. - -An expression specifies a computation that produces a value or location. -Expressions that produce locations are called `l-values`:idx:. An l-value -can denote either a location or the value the location contains, depending on -the context. Expressions whose values can be determined statically are called -`constant expressions`:idx:; they are never l-values. - -A `static error`:idx: is an error that the implementation detects before -program execution. Unless explicitly classified, an error is a static error. - -A `checked runtime error`:idx: is an error that the implementation detects -and reports at runtime. The method for reporting such errors is via *raising -exceptions* or *dying with a fatal error*. However, the implementation -provides a means to disable these runtime checks. See the section pragmas_ -for details. - -Whether a checked runtime error results in an exception or in a fatal error at -runtime is implementation specific. Thus the following program is always -invalid: - -.. code-block:: nim - var a: array[0..1, char] - let i = 5 - try: - a[i] = 'N' - except IndexError: - echo "invalid index" - -An `unchecked runtime error`:idx: is an error that is not guaranteed to be -detected, and can cause the subsequent behavior of the computation to -be arbitrary. Unchecked runtime errors cannot occur if only `safe`:idx: -language features are used. - |