`[Lang]Rewrite`

inherits Object · defined at lang/ast.qn:53

An edit list over one unit's source: collect replacements by node span, apply splices them (back to front, byte-exact — spans are byte offsets) into new source text. Overlapping edits throw. The output is just source: parse it again to verify, eval it to use it.

use std:lang/ast
var src = 'total = 2 + 3'
var rw = [Lang]Rewrite.over:src
([Lang]Parser.parse:src).walk:{ |n|
    (n.kind == #integerLiteral).if:{ rw.replace:n with:((n.at:#value) * 10).s }
}
rw.apply    "* -> total = 20 + 30

Class methods

over:

A rewriter over source (the exact text that was parsed — spans must refer to it).

lang/ast.qn:57

Instance methods

apply

The rewritten source. Edits apply back to front so earlier spans stay valid; two edits that overlap throw a ValueError (zero-width inserts at the same position are fine).

lang/ast.qn:93

delete:

Remove node's span entirely. Answers self.

lang/ast.qn:72

init

Internal.

lang/ast.qn:61

insertAfter: text:String

Insert text immediately after node. Answers self.

lang/ast.qn:83

insertBefore: text:String

Insert text immediately before node. Answers self.

lang/ast.qn:75

replace: with:String

Replace node's exact span with text. Answers self.

lang/ast.qn:64