Error finding collect()

Training
1

I keep getting this error:
training/hello-nextflow → nextflow run hello-workflow.nf
Nextflow 25.04.4 is available - Please consider updating your version to it

N E X T F L O W ~ version 25.04.3

Launching hello-workflow.nf [mad_spence] DSL2 - revision: a4a52ec9fd

[- ] process > sayHello -
[- ] process > convertToUpper -
[- ] process > collectGreetings -
ERROR ~ No such variable: Exception evaluating property ‘collect’ for nextflow.script.ChannelOut, Reason: groovy.lang.MissingPropertyException: No such property: collect for class: groovyx.gpars.dataflow.DataflowBroadcast

– Check script ‘hello-workflow.nf’ at line: 70 or see ‘.nextflow.log’ file for more details

And this is how my workflow looks like in my nf file: workflow {

// create a channel for inputs from a CSV file
greeting_ch = Channel.fromPath(params.greeting)
                    .splitCsv()
                    .map { line -> line[0] }

// emit a greeting
sayHello(greeting_ch)

convertToUpper(sayHello.out)

collectGreetings(convertToUpper.out.collect())
convertToUpper.out.view{ greetings -> "Before collect: $greetings"}
convertToUpper.out.collect.view{ greetings -> "After collect: $greetings"}

}

can’t see where the mistake might be

2

Got it! I didn’t add the () after collect on this line:
convertToUpper.out.collect().view{ greetings → “After collect: $greetings”}

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