Go template comparison operators on missing map key -

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i unable find documentation regarding type of return value when attempting key map in key doesn't exist. go bug tracker appears special 'no value'

i'm trying compare 2 values using eq function gives error if key doesn't exist

example:

var themap := map[string]string{}   var mystruct := struct{mymap map[string]string}{themap}  {{if eq .mymap.keythatdoesntexist "mystring"}}   {{.}} {{end}

results in error calling eq: invalid type comparison

from assume nil value not empty string "" in go itself.

is there simple way compare potentially non-existent map value , value?

use index function:

{{if eq (index .mymap "keythatdoesntexist") "mystring"}}   {{.}} {{end}

playground example

the index function returns 0 value map value type when key not in map. 0 value map in question empty string.


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