Clojure overloaded method resolution for Longs

Question

This behavior makes no sense to me:

user=> (type 1)
java.lang.Long
user=> (type (cast Long 1))
java.lang.Long
user=> (type 1)
java.lang.Long
user=&g         


        

Answer 1

BigDecimal does not have a constructor for Long,

BigDecimal(BigInteger val)

core> (BigDecimal. (BigInteger/ONE))
1M

BigDecimal(BigInteger unscaledVal, int scale)

core> (BigDecimal. BigInteger/ONE 1)
0.1M

BigDecimal(double val)

core> (BigDecimal. (double 1))
1M
core> (BigDecimal. (float 1))
1M
(BigDecimal. Double/MIN_VALUE)

BigDecimal(String val)

core> (BigDecimal. "1")
1M

It's unclear which of these (Long. 1) matches. the clojure.core.bigdec function works on this input by passing it's input to BigDec/valueOf to create the BigDecimal

core>  (bigdec (Long. 1))
1M

uses this call:

(BigDecimal/valueOf (long x))