Nextflow：如何让后续流程读取前序生成的索引文件目录路径

我有三个Nextflow脚本文件：main.nf、index_process.nf和dummy_bwamem.nf。main.nf中指定了索引文件的输出目录，使用BWA比对工具生成索引，测试采用脑膜炎奈瑟菌（Neisseria meningitidis）的小型FASTA基因组文件。由于config.nf无法按预期生成文件，因此代码中未使用它。

各脚本内容 #

main.nf #

params.outdir_index_temp="./bwa_index_temp"
params.outdir_bwa_mem="./bwamem"
params.hg38genome ="/Users/username/Downloads/NM.fasta"

include {bwa_index} from './index_process.nf'
include { align_bwa_mem} from './dummy_bwamem.nf'

workflow {

bwa_index(params.hg38genome, params.outdir_index_temp)
align_bwa_mem(bwa_index.out,params.outdir_index_temp).view()
    
}

index_process.nf #

process bwa_index {

    tag {ref_fasta.name}
    publishDir "${outdir}/", mode:"copy"

    input:
    path ref_fasta
    val outdir 

    output:
    tuple val(ref_fasta.name), path("${ref_fasta.name}.{ann,amb,sa,bwt,pac}")

    """
    bwa index "${ref_fasta}"
    """
}

dummy_bwamem.nf #

process align_bwa_mem {

input :

    tuple val(fasta_name), path(indexfiles) //if you use val(pathindexfiles) you get work/ae/34567890/asdasdad and such

     val(path_index_output) 

    output: stdout

    script:

    """
    echo "$path_index_output $indexfiles\n"
    echo "$fasta_name\n"
    """
}

运行输出 #

nextflow run main.nf 
N E X T F L O W  ~  version 23.04.1
Launching `main.nf`  
 [goofy_cuvier] DSL2 - revision: 03a15979cf
executor >  local (2)
[84/73be26] process > bwa_index (NM.fasta) [100%] 1 of 1 ✔
[a1/75f4d0] process > align_bwa_mem        [100%] 1 of 1 ✔
./bwa_index_temp NM.fasta.amb NM.fasta.ann NM.fasta.bwt NM.fasta.pac NM.fasta.sa
    
NM.fasta

需求说明 #

我需要确保比对流程能读取带完整路径的索引文件，具体路径格式如下：
./bwa_index_temp/NM.fasta.amb ./bwa_index_temp/NM.fasta.ann ./bwa_index_temp/NM.fasta.bwt ./bwa_index_temp/NM.fasta.pac ./bwa_index_temp/NM.fasta.sa

我已自行编写Nextflow代码并在StackOverflow提问，但希望自主探索学习，而非直接获取现成答案。

内容的提问来源于stack exchange，提问作者Death Metal