update string type

src/types/strings.md

@@ -4,53 +4,3 @@
 `len: int`
 Character count of string.
 It is can constant if string is literal. 
-
-## Methods
-`fn has_prefix(self, sub: str): bool`\
-Reports string has prefix as specified substring or not.
-
----
-
-`fn has_suffix(self, sub: str): bool`\
-Reports string has suffix as specified substring or not.
-
----
-
-`fn find(self, sub: str): int`\
-Returns index of first matched item with specified substring, returns -1 if not exist any match.\
-Starts searching at left of string to right.
-
----
-
-`fn rfind(self, sub: str): int`\
-Returns index of first matched item with specified substring, returns -1 if not exist any match.\
-Starts searching at right of string to left.
-
----
-
-`fn ltrim(self, bytes: str): str`\
-Trims string by specified bytes at left. Each character is each byte.
-
----
-
-`fn rtrim(self, bytes: str): str`\
-Trims string by specified bytes at right. Each character is each byte.
-
----
-
-`fn trim(self, bytes: str): str`\
-Trims string by specified bytes at left and right. Each character is each byte.
-
----
-
-`fn split(self, sub: str, n: int): []str`\
-Splits the string into the specified number of parts to the specified substring.\
-Returns empty slice if n is equals to zero.\
-Returns all parts if n less than zero.
-
----
-
-`fn replace(self, sub: str, new: str, n: int): str`\
-Replaces all substrings matching sub in the string with new.\
-Returns same string if n is equals to zero.\
-Replaces all matches if n less than zero.