groovy,closures,fluent,method-chaining , Fluent Groovy syntax using command chaining and maps

Fluent Groovy syntax using command chaining and maps


Tag: groovy,closures,fluent,method-chaining

Given the following Groovy code:

someMap = ['key':{ str -> println "SUCCESS: ${str}" }]
clos = { someMap }

All of the following are legal ways to print SUCCESS: abc:

clos(null)['key'] "abc"
clos null key "abc"
someMap['key'] "abc"

This one, however:

someMap key "abc"

throws a groovy.lang.MissingPropertyException: No such property: key for class: ConsoleScript50.

If clos(null) and someMap both resolve to java.util.LinkedHashMap, then what makes clos null key "abc" legal, but someMap key "abc" not legal?


Groovy understands someMap key "abc" as someMap(key).getAbc(), which won't work. You really need the dot:

someMap.key "abc"

Or square brackets

someMap['key'] "abc"


It seems that Groovy will always disambiguate a token like key as a call parameter (i.e. someMap(key)) if it can.

Yes, it will.

Only if that interpretation doesn't make sense does it instead interpret the token as a property (.key) or map dereference (['key']).

No, Groovy will always understand the second parameter, without dots or parens, as a call parameter. This

function parameter

Is always undertood as


It features no "precedence" over object[key]

If you keep adding stuff without dots or parenthesis to disambiguate, Groovy will keep adding parens and dots as per it's own rules. This:

gimme coffee with sugar and milk

Is understood as


Also this:

clos null key 'abc'

Will always be undertood as



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