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Function

is_error — test if a value is an error

Synopsis

is_error(val: any) -> bool

Description

The is_error function returns true if its argument’s type is an error. is_error(v) is shorthand for kind(v)=="error",

Examples


A simple value is not an error

# spq
values is_error(this)
# input
1
# expected output
false

An error value is an error

# spq
values is_error(this)
# input
error(1)
# expected output
true

Convert an error string into a record with an indicator and a message

# spq
values {err:is_error(this),message:under(this)}
# input
"not an error"
error("an error")
# expected output
{err:false,message:"not an error"}
{err:true,message:"an error"}