Added functions to the Char module to check common character properties.

src/core/CCChar.ml

@@ -23,3 +23,12 @@ module Infix = struct
 end
 
 include Infix
+
+let is_uppercase_ascii c = c > '\064' && c < '\091'
+let is_lowercase_ascii c = c > '\096' && c < '\123'
+
+let is_letter_ascii c =
+  (is_lowercase_ascii [@inlined]) c || (is_uppercase_ascii [@inlined]) c
+
+let is_digit_ascii c = c > '\047' && c < '\058'
+let is_whitespace_ascii c = c = '\032' || (c > '\008' && c < '\014')

src/core/CCChar.mli

@@ -40,6 +40,32 @@ val pp_buf : Buffer.t -> t -> unit
 val pp : Format.formatter -> t -> unit
 (** Renamed from [print] since 2.0. *)
 
+val is_uppercase_ascii : t -> bool
+(** [is_uppercase_ascii c] is true exactly when  [c] is an
+    uppercase ASCII character, i.e. ['\064'] < [c] < ['\091'].
+    @since 3.16 *)
+
+val is_lowercase_ascii : t -> bool
+(** [is_lowercase_ascii c] is true exactly when [c] is a
+    lowercase ASCII character, i.e. ['\097'] < [c] < ['\123'].
+    @since 3.16 *)
+
+val is_letter_ascii : t -> bool
+(** [is_letter_ascii c] is true exactly when [c] is an ASCII
+    letter, i.e. [is_uppercase_ascii c || is_lowercase_ascii c].
+    @since 3.16 *)
+
+val is_digit_ascii : t -> bool
+(** [is_digit_ascii c] is true exactly when [c] is an
+    ASCII digit, i.e. ['\047'] < [c] < ['\058'].
+    @since 3.16 *)
+
+val is_whitespace_ascii : t -> bool
+(** [is_whitespace_ascii c] is true exactly when [c] is an ASCII
+    whitespace character as defined by Unicode, i.e. either [c = ' ']
+    or ['\008'] < [c] < ['\014'].
+    @since 3.16 *)
+
 (** {2 Infix Operators}
 
     @since 3.3 *)