RFC 0021: Percent String Array Literal with Interpolation - #21
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Co-authored-by: Julien Portalier <julien@portalier.com>
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| %W[foo #{"bar"}baz#{"bab"} qux] # => ["foo", "barbazbab", "qux"] | ||
| %W[foo _#{"bar"}_ baz] # => ["foo", "_bar_", "baz"] | ||
| %W[foo #{"bar baz"} qux] # => ["foo", "bar baz", "qux"] | ||
| ``` |
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IMO this should show the immediate transformations performed by the compiler, more specifically the parser, rather than the final results of the expressions. If I have to guess, this would mean:
["foo", "#{1 + 1}", "baz"] of ::String
["foo", "#{"bar"}baz#{"bab"}", "qux"] of ::Stringand also splat elements would be retained verbatim, without introducing another StringInterpolation node:
["foo", *%w[bar baz], "qux"] of ::String
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Good point. The reference-level explanation is actually just an extended guide-level and does not explain the technical details. I'll expand on that 👍
The markdownlint config has been adapted from the established https://github.com/crystal-lang/crystal-website/blob/27838d03a6be4d375d1c123a246446e97050add5/.markdownlint.yaml
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This is a bit of code cleanup, avoiding unnecessary intermediaries and removing duplication. It's in preparation for implementing `%W` string array literals (crystal-lang/rfcs#21).
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This pull request has been mentioned on Crystal Forum. There might be relevant details there: https://forum.crystal-lang.org/t/rfc-0021-percent-string-array-literal-with-interpolation/8772/1 |
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This is a plain refactoring to extract behaviour into helper methods. It helps structure the code and prepares for reusing these helpers to implement interpolation for string array literals ([RFC 0021](crystal-lang/rfcs#21)).
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…16747) Continuation of #16720, but extracted into a separate commit for a cleaner diff because of overlap. This is a plain refactoring to extract behaviour into helper methods. It helps structure the code and prepares for reusing these helpers to implement interpolation for string array literals ([RFC 0021](crystal-lang/rfcs#21)).
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Previously, string array literal parsing used a custom implementation, combined with a custom lexer mode (`next_string_array_token`). This patch changes that to reuse the same parser and lexer features as other string literals. This standardization removes an extra concept and thus reduces code surface area. In return, we're adding some conditionals for this specific literal type into the standard implementations. This increases complexity a little bit, but it's still fairly easy to reason about and a common pattern in the parser. Combining the parsing of all string-related literals clearly shows their differences (in the form of such conditionals) and ensures consistent behaviour. In particular, this change establishes standard behaviour for escape characters, and thus fixes #12277 However, it's unclear whether we accept this behaviour change (see #12277 (comment)). If not, we need to implement a non-standard escape algorithm to ensure backwards-compatibility. The main motivation for this refactor is that it opens the path for implementing string literals with interpolation ([RFC 0021](crystal-lang/rfcs#21)). Co-authored-by: Julien Portalier <julien@portalier.com>
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This implements [RFC 21]. [RFC 21]: crystal-lang/rfcs#21
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Preview: https://github.com/crystal-lang/rfcs/blob/rfc/percent-array-literal-interpolation/text/0021-percent-array-literal-interpolation.md