/fusion/timestamp

< procedure

(< a b)

Returns true if a is less than b. Numbers are compared without regard to precision or negative zeros; if the values have different concrete types they are both coerced to decimal. Timestamps are compared to each other without regard to precision or local offset. Annotations are ignored.

Warning: The behavior of this procedure is undefined for values +inf, -inf, and nan. See issue #64.

<= procedure

(<= a b)

Returns true if a is less than or equal to b. Numbers are compared without regard to precision or negative zeros; if the values have different concrete types they are both coerced to decimal. Timestamps are compared to each other without regard to precision or local offset. Annotations are ignored.

Warning: The behavior of this procedure is undefined for values +inf, -inf, and nan. See issue #64.

= procedure

(= left right)

Returns true if the arguments are equivalent in shape and content, possibly by coercing values to a common type. Annotations and precision are ignored.

Any value is = to itself.
Nulls of any type are = to each other.
Bools are = in the obvious way.
Numbers are = when they represent the same numeric value, without regard to precision or negative zeros. When a float is compared to an int or decimal, it is coerced to a decimal.
Timestamps are = when they represent the same point-in-time, without regard to precision or local offset.
Strings and symbols are = (interchangably) when they contain the same sequence of code points.
Blobs and clobs are = (interchangably) when they contain the same sequence of bytes.
Pairs are = when their heads and tails are =.
Sequences are = when they have the same size, and elements at the same index are =.
Structs are = when they have the same set of field names, and each name maps to a set of elements that are =.
Void is = only to itself.
Exceptions are not thrown due to mismatched types; instead the result is false.

For example:

(= null (quote a::null))             --> true
(= null null.clob)                   --> true
(= 1 1.00)                           --> true
(= 0 -0e-3)                          --> true
(= 2014T 2014-01-01T02:00+02:00)     --> true
(= 2014T 2014)                       --> false

(= "text" (quote text))              --> true
(= "text" (quote a::"text"))         --> true

(= [1, 2] (sexp 1 2.00))             --> true
(= null.list [])                     --> false

(= (struct "f" 1) (mutable_struct "f" 1.0))   --> true
(= {f:1, f:1} {f:1})                          --> false

At present, the coercion of float to decimal is precise, without rounding to approximate a prettier decimal form. This may lead to strange behavior since most decimal numbers don't have a precise binary representation:

(= 1.2 1.2e0)  --> false
(= 1.5 1.5e0)  --> true

It's possible this may change in a future release.

Warning: The behavior of this procedure is undefined for values +inf, -inf, and nan. See issue #64.

> procedure

(> a b)

Returns true if a is greater than b. Numbers are compared without regard to precision or negative zeros; if the values have different concrete types they are both coerced to decimal. Timestamps are compared to each other without regard to precision or local offset. Annotations are ignored.

Warning: The behavior of this procedure is undefined for values +inf, -inf, and nan. See issue #64.

>= procedure

(>= a b)

Returns true if a is greater than or equal to b. Numbers are compared without regard to precision or negative zeros; if the values have different concrete types they are both coerced to decimal. Timestamps are compared to each other without regard to precision or local offset. Annotations are ignored.

Warning: The behavior of this procedure is undefined for values +inf, -inf, and nan. See issue #64.

adjust_day procedure

(adjust_day ts period)

Returns a timestamp that's period days after (or before, if negative) ts. The result will have the same precision and local offset.