Ich habe versucht, die Build-Markup-Funktion mit der vorherigen Antwort zu verfeinern:Wie binde ich an jeden Kontext?

build-markup: func [
    {Return markup text replacing <%tags%> with their evaluated results.} 
    content [string! file! url!] 
    /repeat block-fields block-values
    /quiet "Do not show errors in the output." 
    /local out eval value
][

  either not repeat [
      content: either string? content [copy content] [read content] 
      out: make string! 126 
      eval: func [val /local tmp] [
          either error? set/any 'tmp try [do val] [
              if not quiet [
                  tmp: disarm :tmp 
                  append out reform ["***ERROR" tmp/id "in:" val]
              ]
          ] [
              if not unset? get/any 'tmp [append out :tmp]
          ]
      ] 
      parse/all content [
          any [
              end break 
              | "<%" [copy value to "%>" 2 skip | copy value to end] (eval value) 
              | copy value [to "<%" | to end] (append out value)
          ]
      ]
    ][        
        probe :block-fields
        foreach :block-fields block-values [
          print get pick :block-fields 1
          print get pick :block-fields 2
        ]
    ] 
    out
]

c: [a b]
template: "<%a%> <%b%>"
build-markup/repeat template :c [1 2 3 4]

Output ist nicht das, was ich will:

>> c: [a b]
== [a b]
>> template: "<%a%> <%b%>"
== "<%a%> <%b%>"
>> build-markup/repeat template :c [1 2 3 4]
[a b]
1
1 a b
1
1 a b

whereas hätte ich erwartet

1
2
3
4

So wie soll ich das korrigieren?