Forms and builtins
Strings and symbols
12 builtins. Every example below ran on the evaluator, and the result shown is what it returned.
string?
arity 1(string? x)
Is the argument a string?
(list (string? "a") (string? 'a))=>(#t #f)
symbol?
arity 1(symbol? x)
Is the argument a symbol?
(list (symbol? 'a) (symbol? "a"))=>(#t #f)
string-append
arity 0+(string-append s ...)
Joins strings.
(string-append "foo" "bar")=>"foobar"
string-length
arity 1(string-length s)
Number of characters (codepoints).
(string-length "héllo")=>5
substring
arity 2-3(substring s start [end])
(substring s start end): characters from start up to, not including, end.
(substring "hello world" 6 11)=>"world"
string=?
arity 1+(string=? s t ...)
Are the strings equal?
(string=? "abc" "abc")=>#t
string<?
arity 1+(string<? s t ...)
Are the strings in increasing order?
(string<? "apple" "banana")=>#t
string>?
arity 1+(string>? s t ...)
Are the strings in decreasing order?
(string>? "apple" "banana")=>#f
string-upcase
arity 1(string-upcase s)
Upper-cased copy.
(string-upcase "shout")=>"SHOUT"
string-downcase
arity 1(string-downcase s)
Lower-cased copy.
(string-downcase "QUIET")=>"quiet"
string->symbol
arity 1(string->symbol s)
The symbol with this name.
(string->symbol "hello")=>hello
symbol->string
arity 1(symbol->string sym)
The symbol's name.
(symbol->string 'hello)=>"hello"