Transpilers/Syntax/RegexLiteral.psx.ps1
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<# .SYNOPSIS Regex Literal Transpiler .DESCRIPTION Allows for Regex Literals within PipeScript. Regex Literals are strings enclosed within slashes. The ending slash may be followed by ```[Text.RegularExpressions.RegexOptions]```. .Example { '/[a|b]/' } | .>PipeScript .EXAMPLE { "/[$a|$b]/" } | .>PipeScript .EXAMPLE {@' / # Heredocs Regex literals will have IgnorePatternWhitespace by default, which allows comments ^ # Match the string start (?<indent>\s{0,1}) / '@ } | .>PipeScript .EXAMPLE { $Keywords = "looking", "for", "these", "words" @" / # Double quoted heredocs can still contain variables [\s\p{P}]{0,1} # Whitespace or punctuation $($Keywords -join '|') # followed by keywords [\s\p{P}]{0,1} # followed by whitespace or punctuation / "@ } | .>PipeScript #> [ValidatePattern(@' ^ # Start anchor (?<HereDoc>@){0,1} # Optional heredoc start ['`"] # String start (?(HereDoc)([\r\n]{1,2})) # If we found a heredoc, the next portion of the match must be 1-2 newlines/carriage returns / # Followed by a slash '@, Options='IgnoreCase,IgnorePatternWhitespace')] [ValidatePattern(@' / # closing slash (?<Options>[\w,]+){0,1} # optional options (?(HereDoc)([\r\n]{1,2})) # If we found a heredoc, the next portion of the match must be 1-2 newlines/carriage returns ['`"] (?<HereDoc>@){0,1} # Optional heredoc end $ # string end. '@, Options='IgnoreCase,IgnorePatternWhitespace, RightToLeft')] param( [Parameter(Mandatory,ValueFromPipeline,ParameterSetName='StringConstantExpressionAST')] [Management.Automation.Language.StringConstantExpressionAST] $StringConstantExpression, [Parameter(Mandatory,ValueFromPipeline,ParameterSetName='ExpandableStringExpressionAst')] [Management.Automation.Language.ExpandableStringExpressionAst] $ExpandableStringExpression ) begin { $startRegex, $endRegex, $null = foreach ($attr in $MyInvocation.MyCommand.ScriptBlock.Attributes) { if (-not $attr.RegexPattern) { continue } [Regex]::new($attr.RegexPattern, $attr.Options) } } process { $StringExpr, $stringType = if ($StringConstantExpression ) { $StringConstantExpression.Extent.ToString(), $StringConstantExpression.StringConstantType } else { $ExpandableStringExpression.Extent.ToString(), $ExpandableStringExpression.StringConstantType } $sparseStringExpr = $StringExpr -replace $startRegex -replace $endRegex $null = $StringExpr -match $endRegex $stringStart, $stringEnd = if ($stringType -eq 'SingleQuotedHereString') { "@'" + [Environment]::NewLine [Environment]::NewLine + "'@" } elseif ($stringType -eq 'DoubleQuotedHereString') { '@"' + [Environment]::NewLine [Environment]::NewLine + '"@' } elseif ($stringType -eq 'SingleQuoted' ) { "'" "'" } elseif ($stringType -eq 'DoubleQuoted') { '"' '"' } $recreatedString = $stringStart + $sparseStringExpr + $stringEnd $optionStr = if ($matches.Options) { "'$($matches.Options)'" } else { if ($stringType -like '*here*') { "'IgnorePatternWhitespace,IgnoreCase'" } else { "'IgnoreCase'" } } [scriptblock]::Create("[regex]::new($recreatedString, $optionStr)") } |