log.info "fastq files : ${params.fastq}" Channel .fromPath( params.fastq ) .ifEmpty { error "Cannot find any fastq files matching: ${params.fastq}" } .set { fastq_files } process adaptor_removal { tag "$reads.baseName" input: file reads from fastq_files output: file "*_cut.fastq.gz" into fastq_files_cut script: """ cutadapt -a AGATCGGAAGAG -g CTCTTCCGATCT\ -o ${reads.baseName}_cut.fastq.gz \ ${reads} > ${reads.baseName}_report.txt """ }