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Edit summary for version 37 :
New JS implementation by user [programming-idioms.org]

Version 36

Version 37

Idiom #59 Write to standard error stream

Print the message "x is negative" to standard error (stderr), with integer x value substitution (e.g. "-2 is negative").

Idiom #59 Write to standard error stream

Print the message "x is negative" to standard error (stderr), with integer x value substitution (e.g. "-2 is negative").

Code
console.error(x, "is negative");
Doc URL
https://console.spec.whatwg.org/#error