Parameter: compose runtime text parameter

Tool

Use toolshed.g2.bx.psu.edu/repos/iuc/compose_text_param/compose_text_param/0.1.1 when a downstream tool parameter must be a runtime-built text string rather than a fixed literal.

The tool concatenates ordered components into out1, which then connects into text-like downstream parameters such as cond, columnList, regions, text_input, or read-group IDs.

When to reach for it

Use this when constants and runtime values must become one exact string: c4 >= <threshold>, cN,cM, genomic ranges, read-group IDs, or config lines.

Use it before tools whose target parameter is text but whose value depends on workflow inputs or upstream scalar parameter steps.

Do not use this for enum-to-flag mapping; use map-workflow-enum-to-tool-parameter.

Do not use this for tabular string computation that should remain a dataset column; use tabular-compute-new-column or a tabular text-processing pattern.

Operation Boundary

This pattern covers composing a text parameter at workflow runtime from ordered literal and connected scalar pieces.

It does not cover reading scalar values from files, mapping enum values to dialects, row-wise tabular string computation, or custom wrapper authoring.

Parameters

• components: ordered repeat; order is the output string order.
• components[].param_type.select_param_type: observed values include text, integer, and float.
• Literal text components carry component_value as the exact string to insert.
• Runtime components carry component_value: { __class__: ConnectedValue } and have a matching in: connection such as components_1|param_type|component_value.
• Output out1: connect to the downstream text parameter.

Preserve spaces, commas, prefixes, and comparison operators exactly in literal chunks. The composer does not understand downstream syntax.

Idiomatic Shapes

Filter predicate:

"c4 >= " + integer threshold -> Filter1.cond

Dynamic column list:

"c" + integer + ",c" + integer -> Cut1.columnList

Config line:

"pull_coord1_rate = " + float -> add_line_to_file.text_input

Region or read-group string:

runtime start/end text + literal separators or pool suffix -> downstream text parameter

These snippets are conceptual; use the gxformat2 exemplars for exact serialized shapes.

Pitfalls

• Component order is semantic. Reordering components without matching connections changes the generated string.
• Literal whitespace matters. Leading and trailing spaces in config-line chunks are meaningful.
• There is no downstream syntax validation. compose_text_param can build an invalid Filter1.cond, invalid Cut1.columnList, or invalid genomic range.
• Connected text is not a dataset. Connect out1 to a tool parameter, not a dataset input.
• Do not replace map-workflow-enum-to-tool-parameter. If the operation is mapping stranded to a flag or snippet, map first; compose only when the final task is concatenation.
• Do not confuse row-wise string construction with runtime parameter composition. If each input row needs a computed string, use tabular tools.

See Also

• iwc-parameter-derivation-survey — Candidate E decision record.
• derive-parameter-from-file — when runtime scalar values start as one-value datasets.
• map-workflow-enum-to-tool-parameter — when a workflow-facing enum must become a downstream dialect.
• tabular-filter-by-column-value — common downstream consumer via Filter1.cond.
• tabular-cut-and-reorder-columns — common downstream consumer via Cut1.columnList.