Refactored file() method to use 'if' branch instead of 'switch'
Refactored file() method to use 'if' branch instead of 'switch'

heuermh/nextflow,robsyme/nextflow,nextflow-io/nextflow,robsyme/nextflow,nextflow-io/nextflow,heuermh/nextflow,nextflow-io/nextflow,nextflow-io/nextflow,heuermh/nextflow,heuermh/nextflow,robsyme/nextflow,robsyme/nextflow,heuermh/nextflow,nextflow-io/nextflow,robsyme/nextflow