add ascii procedure docs

Author: wassup05

doc/specs/stdlib_ascii.md

@@ -184,8 +184,370 @@ All the ascii whitespace characters (space, horizontal tab, vertical tab, carria
 
 ## Specification of the `stdlib_ascii` procedures
 
-@note Specification of procedures is currently incomplete.
+### `is_alpha`
 
+#### Status
+
+Experimental
+
+#### Description
+
+Checks whether input character is an ASCII letter (A-Z, a-z).
+
+#### Syntax
+
+`res =` [[stdlib_ascii(module):is_alpha(function)]] `(c)`
+
+#### Class
+
+Elemental function.
+
+#### Argument
+
+`c`: shall be an intrinsic `character(len=1)` type. It is an `intent(in)` argument.
+
+#### Result value
+
+The result is a `logical`.
+
+### `is_alphanum`
+
+#### Status
+
+Experimental
+
+#### Description
+
+Checks whether input character is an ASCII letter or a number (A-Z, a-z, 0-9).
+
+#### Syntax
+
+`res =` [[stdlib_ascii(module):is_alphanum(function)]] `(c)`
+
+#### Class
+
+Elemental function.
+
+#### Argument
+
+`c`: shall be an intrinsic `character(len=1)` type. It is an `intent(in)` argument.
+
+#### Result value
+
+The result is a `logical`.
+
+### `is_ascii`
+
+#### Status
+
+Experimental
+
+#### Description
+
+Checks whether input character is in the ASCII character set i.e in the range 0-128.
+
+#### Syntax
+
+`res =` [[stdlib_ascii(module):is_ascii(function)]] `(c)`
+
+#### Class
+
+Elemental function.
+
+#### Argument
+
+`c`: shall be an intrinsic `character(len=1)` type. It is an `intent(in)` argument.
+
+#### Result value
+
+The result is a `logical`.
+
+### `is_control`
+
+#### Status
+
+Experimental
+
+#### Description
+
+Checks whether input character is a control character.
+
+#### Syntax
+
+`res =` [[stdlib_ascii(module):is_control(function)]] `(c)`
+
+#### Class
+
+Elemental function.
+
+#### Argument
+
+`c`: shall be an intrinsic `character(len=1)` type. It is an `intent(in)` argument.
+
+#### Result value
+
+The result is a `logical`.
+
+### `is_digit`
+
+#### Status
+
+Experimental
+
+#### Description
+
+Checks whether input character is a digit (0-9).
+
+#### Syntax
+
+`res =` [[stdlib_ascii(module):is_digit(function)]] `(c)`
+
+#### Class
+
+Elemental function.
+
+#### Argument
+
+`c`: shall be an intrinsic `character(len=1)` type. It is an `intent(in)` argument.
+
+#### Result value
+
+The result is a `logical`.
+
+### `is_octal_digit`
+
+#### Status
+
+Experimental
+
+#### Description
+
+Checks whether input character is an octal digit (0-7)
+
+#### Syntax
+
+`res =` [[stdlib_ascii(module):is_octal_digit(function)]] `(c)`
+
+#### Class
+
+Elemental function.
+
+#### Argument
+
+`c`: shall be an intrinsic `character(len=1)` type. It is an `intent(in)` argument.
+
+#### Result value
+
+The result is a `logical`.
+
+### `is_hex_digit`
+
+#### Status
+
+Experimental
+
+#### Description
+
+Checks whether input character is a hexadecimal digit (0-9, A-F, a-f).
+
+#### Syntax
+
+`res =` [[stdlib_ascii(module):is_hex_digit(function)]] `(c)`
+
+#### Class
+
+Elemental function.
+
+#### Argument
+
+`c`: shall be an intrinsic `character(len=1)` type. It is an `intent(in)` argument.
+
+#### Result value
+
+The result is a `logical`.
+
+### `is_punctuation`
+
+#### Status
+
+Experimental
+
+#### Description
+
+Checks whether input character is a punctuation character.
+
+#### Syntax
+
+`res =` [[stdlib_ascii(module):is_punctuation(function)]] `(c)`
+
+#### Class
+
+Elemental function.
+
+#### Argument
+
+`c`: shall be an intrinsic `character(len=1)` type. It is an `intent(in)` argument.
+
+#### Result value
+
+The result is a `logical`.
+
+### `is_graphical`
+
+#### Status
+
+Experimental
+
+#### Description
+
+Checks whether input character is a graphical character (printable other than the space character).
+
+#### Syntax
+
+`res =` [[stdlib_ascii(module):is_graphical(function)]] `(c)`
+
+#### Class
+
+Elemental function.
+
+#### Argument
+
+`c`: shall be an intrinsic `character(len=1)` type. It is an `intent(in)` argument.
+
+#### Result value
+
+The result is a `logical`.
+
+### `is_printable`
+
+#### Status
+
+Experimental
+
+#### Description
+
+Checks whether input character is a printable character (including the space character).
+
+#### Syntax
+
+`res =` [[stdlib_ascii(module):is_printable(function)]] `(c)`
+
+#### Class
+
+Elemental function.
+
+#### Argument
+
+`c`: shall be an intrinsic `character(len=1)` type. It is an `intent(in)` argument.
+
+#### Result value
+
+The result is a `logical`.
+
+### `is_lower`
+
+#### Status
+
+Experimental
+
+#### Description
+
+Checks whether input character is a lowercase ASCII letter (a-z).
+
+#### Syntax
+
+`res =` [[stdlib_ascii(module):is_lower(function)]] `(c)`
+
+#### Class
+
+Elemental function.
+
+#### Argument
+
+`c`: shall be an intrinsic `character(len=1)` type. It is an `intent(in)` argument.
+
+#### Result value
+
+The result is a `logical`.
+
+### `is_upper`
+
+#### Status
+
+Experimental
+
+#### Description
+
+Checks whether input character is an uppercase ASCII letter (A-Z).
+
+#### Syntax
+
+`res =` [[stdlib_ascii(module):is_upper(function)]] `(c)`
+
+#### Class
+
+Elemental function.
+
+#### Argument
+
+`c`: shall be an intrinsic `character(len=1)` type. It is an `intent(in)` argument.
+
+#### Result value
+
+The result is a `logical`.
+
+### `is_white`
+
+#### Status
+
+Experimental
+
+#### Description
+
+Checks whether input character is a whitespace character (which includes space, horizontal tab, vertical tab,
+carriage return, linefeed and form feed characters)
+
+#### Syntax
+
+`res =` [[stdlib_ascii(module):is_white(function)]] `(c)`
+
+#### Class
+
+Elemental function.
+
+#### Argument
+
+`c`: shall be an intrinsic `character(len=1)` type. It is an `intent(in)` argument.
+
+#### Result value
+
+The result is a `logical`.
+
+### `is_blank`
+
+#### Status
+
+Experimental
+
+#### Description
+
+Checks whether input character is a blank character (which includes space and tabs).
+
+#### Syntax
+
+`res =` [[stdlib_ascii(module):is_blank(function)]] `(c)`
+
+#### Class
+
+Elemental function.
+
+#### Argument
+
+`c`: shall be an intrinsic `character(len=1)` type. It is an `intent(in)` argument.
+
+#### Result value
+
+The result is a `logical`.
 
 ### `to_lower`
 
@@ -217,7 +579,7 @@ The result is an intrinsic character type of the same length as `string`.
 
 ```fortran
 {!example/ascii/example_ascii_to_lower.f90!}
-``` 
+```
 
 ### `to_upper`