Initial commit

LICENSE.txt

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+                   GNU LESSER GENERAL PUBLIC LICENSE
+                       Version 3, 29 June 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+
+  This version of the GNU Lesser General Public License incorporates
+the terms and conditions of version 3 of the GNU General Public
+License, supplemented by the additional permissions listed below.
+
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+
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+General Public License, and the "GNU GPL" refers to version 3 of the GNU
+General Public License.
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+Library.

README.md

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+Type Checking
+=============
+
+This is a backport of most of AutoHotkey v2’s type checking features to v1.  They are useful for validation and dispatching.
+
+[Design](docs/Design.md) contains the reasons for the design decisions.
+
+
+## Installation
+
+The files in [src](src) must be placed in a [library directory](https://www.autohotkey.com/docs/Functions.htm#lib).
+
+
+## Usage
+
+Directly calling a function will cause its library to be auto-included.  If the function is only called dynamically or indirectly, its library must be explicitly included.
+
+[`IsInteger(Value)`](docs/IsInteger.md)
+
+[`IsFloat(Value)`](docs/IsFloat.md)
+
+[`IsNumber(Value)`](docs/IsNumber.md)
+
+[`IsString(Value)`](docs/IsString.md)
+
+[`Type(Value)`](docs/Type.md)
+
+[`IsInstance(Value, Class)`](docs/IsInstance.md) is v2’s `is` operator as a function.
+
+[`HasProp(Value, Name)`](docs/HasProp.md)
+
+[`HasMethod(Value, Name)`](docs/HasMethod.md)
+
+Be aware that these functions do not recognize implicitly-defined members, except for `base`, of primitives or user-defined types.

docs/Design.md

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+I chose not to recognize implicitly-defined members, except for `base`, of primitives or user-defined types because I do not want all primitives and user-defined types to be mistaken for collections.
+
+Implicitly-defined members of Objects (including Arrays) are recognized because they are collections.
+
+I made an exception for `base` because it is useful on any supported type.
+
+I did not distinguish Objects, Arrays, and Exceptions for several reasons:
+* They are the same type in AutoHotkey v1.  Only their contents differ.
+* When AutoHotkey v2’s type system was more similar to v1, its `Type(Value)` function also returned `"Object"` for all of them.
+* It is useful to know that they are the same type because it reveals how to construct them and what operations are compatible with them.
+* They cannot reliably be distinguished.  An empty Object and Array are indistinguishable.
+* When context makes apparent which is expected, they can still be validated with the help of this library.
+* Recognizing Arrays by their contents is very inefficient.

docs/HasMethod.md

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+`HasMethod(Value, Name)` returns whether `Value` has a method identified by `Name`.  `Value` must not be a COM object.
+
+If `Value` is a primitive (Number or String) type, it will examine the [default base object](https://www.autohotkey.com/docs/Objects.htm#Default_Base_Object).
+
+It can recognize methods identified by objects.
+
+This function is useful for validating [interfaces](https://en.wikipedia.org/wiki/Interface_(computing)#In_object-oriented_languages) for [ad hoc polymorphism](https://en.wikipedia.org/wiki/Ad_hoc_polymorphism).
+
+#### Examples
+```AutoHotkey
+Object := {}
+
+F(this)
+{
+}
+
+HasMethod(Func("HasMethod"), "Call")      ; 1
+HasMethod([], "_NewEnum")                 ; 1
+HasMethod(0, "Wrong")                     ; 0
+HasMethod({(Object): Func("F")}, Object)  ; 1
+```

docs/HasProp.md

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+`HasProp(Value, Name)` returns whether `Value` has a property identified by `Name`.  `Value` must not be a COM object.
+
+If `Value` is a primitive (Number or String) type, it will examine the [default base object](https://www.autohotkey.com/docs/Objects.htm#Default_Base_Object).
+
+It can recognize properties identified by objects.
+
+This function is useful for validating [interfaces](https://en.wikipedia.org/wiki/Interface_(computing)#In_object-oriented_languages) for [ad hoc polymorphism](https://en.wikipedia.org/wiki/Ad_hoc_polymorphism).
+
+#### Examples
+```AutoHotkey
+Object := {}
+
+HasProp({}, "X")                ; 0
+HasProp({"X": 1}, "X")          ; 1
+HasProp(0, "base")              ; 1
+HasProp({(Object): 1}, Object)  ; 1
+HasProp({{}: 1}, Object)        ; 0
+```

docs/IsFloat.md

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+`IsFloat(Value)` returns whether `Value` is a floating-point value.
+
+It returns `true` for `-inf`, `inf`, and `nan`.  AutoHotkey does not have literals for these values, but calculations can produce them.
+
+#### Examples
+```AutoHotkey
+A   := 1.0
+B   := 2
+C   := "nan"
+Inf := 9.9 ** 999
+NaN := Inf - Inf
+
+IsFloat(A)    ; 1
+IsFloat(B)    ; 0
+IsFloat(C)    ; 0
+IsFloat(Inf)  ; 1
+IsFloat(NaN)  ; 1
+```

docs/IsInstance.md

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+`IsInstance(Value, Class)` returns whether `Value` is an instance of `Class`.  `Class` must be a user-defined class.
+
+This function is useful for validating [substitutability](https://en.wikipedia.org/wiki/Liskov_substitution_principle) for [subtype polymorphism](https://en.wikipedia.org/wiki/Subtyping), assuming your type hierarchy is correct.
+
+#### Examples
+```AutoHotkey
+class A
+{
+}
+
+class B
+{
+}
+
+IsInstance(new A(), A)  ; 1
+IsInstance(new A(), B)  ; 0
+```

docs/IsInteger.md

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+`IsInteger(Value)` returns whether `Value` is an integer.
+
+#### Examples
+```AutoHotkey
+A   := 1.0
+B   := 2
+C   := "nan"
+Inf := 9.9 ** 999
+NaN := Inf - Inf
+
+IsInteger(A)    ; 0
+IsInteger(B)    ; 1
+IsInteger(C)    ; 0
+IsInteger(Inf)  ; 0
+IsInteger(NaN)  ; 0
+```

docs/IsNumber.md

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+`IsNumber(Value)` returns whether `Value` is a floating-point value or integer.
+
+#### Examples
+```AutoHotkey
+A   := 1.0
+B   := 2
+C   := "nan"
+Inf := 9.9 ** 999
+NaN := Inf - Inf
+
+IsNumber(A)    ; 1
+IsNumber(B)    ; 1
+IsNumber(C)    ; 0
+IsNumber(Inf)  ; 1
+IsNumber(NaN)  ; 1
+```

docs/IsString.md

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+`IsString(Value)` returns whether `Value` is a string.
+
+#### Examples
+```AutoHotkey
+A      := 1.0
+B      := 2
+C      := "nan"
+Inf    := 9.9 ** 999
+NaN    := Inf - Inf
+Object := {}
+
+IsString(A)       ; 1
+IsString(B)       ; 1
+IsString(C)       ; 1
+IsString(Inf)     ; 1
+IsString(NaN)     ; 1
+IsString(Object)  ; 0
+```

docs/Type.md

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+`Type(Value)` returns the type name of `Value`.
+
+This function is useful for reporting type errors and dispatching in the face of AutoHotkey v1’s incorrect type hierarchy and inconsistent interfaces.
+
+#### Examples
+```AutoHotkey
+A := 1.0
+B := 2
+C := "nan"
+
+Type(A)  ; "Float"
+Type(B)  ; "Integer"
+Type(C)  ; "String"
+```