next: Predefined Bounds

Bounds

Bounds define a lower bound, upper bound, or inequality for a certain value. They work on numbers, strings, bytes, and and null.

The bound is defined for all values for which the corresponding comparison operation is define. For instance >5.0 allows all floating point values greater than 5.0, whereas <0 allows all negative numbers (int or float).

bounds.cue

rn :: >=3 & <8        // type int | float
ri :: >=3 & <8 & int  // type int
rf :: >=3 & <=8.0     // type float
rs :: >="a" & <"mo"

a: rn & 3.5
b: ri & 3.5
c: rf & 3
d: rs & "ma"
e: rs & "mu"

r1: rn & >=5 & <10

$ cue eval -ic bounds.cue

a:  3.5
b:  _|_ // conflicting values ri and 3.5 (mismatched types int and float)
c:  3
d:  "ma"
e:  _|_ // invalid value "mu" (out of bound <"mo")
r1: >=5 & <8