TheET runtime library is not dependent on another runtime libraries.(such as C,..)

• Argument(s) : input(char)
• Return : char
• Goal : can convert your character into uppercase letter.

• Argument(s) : input(char)
• Return : char
• Goal : can convert your character into lowercase letter.

• Argument(s) : first-input(char) , second-input(char)
• Return : bool
• Goal : Examines the two-character equality.

• Argument(s) : first-input(char) , second-input(char)
• Return : int8
• Goal : Compare the two-character.

• Argument(s) : input(char) , time(usize)
• Return : char
• Goal : Repeat a character.

• Argument(s) : input(string)
• Return : string
• Goal : can convert your string into uppercase letters.

• Argument(s) : input(string)
• Return : string
• Goal : can convert your string into lowercase letters.

• Argument(s) : input(string) , search(char)
• Return : bool
• Goal : Search a char in string.

• Argument(s) : input(string) , search(string)
• Return : bool
• Goal : Search a string in string.

• Argument(s) : input(string) , search(char) , replace(char)
• Return : string
• Goal : Repeat a character to another character in a text.

• Argument(s) : input(string) , search(string) , replace(string)
• Return : string
• Goal : Repeat a string to another string in a text.

• Argument(s) : first-input(string) , second-input(string)
• Return : bool
• Goal : Examines the two-string equality.

• Argument(s) : first-input(string) , second-input(string)
• Return : bool
• Goal : Compare the two-string.

• Argument(s) : input(string) , from(int64) , to(int64)
• Return : string
• Goal : Getting a limited part of a text string.(begin from $from)

• Argument(s) : input(string) , length(size)
• Return : string
• Goal : Getting a limited part of a text string.(begin from 0)

• Argument(s) : input(string)
• Return : usize
• Goal : Calculate the string length

• Argument(s) : input(string)
• Return : usize
• Goal : Calculate the string length(support UTF-8 characters)

• Argument(s) : input(string)
• Return : char[]
• Goal : Convert string into characters array.