Add log-resyntax-rule-condition (#490)

Author: jackfirth

private/logger.rkt

@@ -6,7 +6,26 @@
          log-resyntax-warning
          log-resyntax-info
          log-resyntax-debug
+         log-resyntax-rule-condition
          resyntax-logger)
 
 
+(require (for-syntax racket/base)
+         syntax/parse/define)
+
+
+;@----------------------------------------------------------------------------------------------------
+
+
 (define-logger resyntax)
+
+
+(define (log-resyntax-rule-condition-impl v #:line line-num #:datum datum)
+  (unless v
+    (log-resyntax-debug "rule condition ~a on line ~a failed" datum line-num))
+  v)
+
+
+(define-syntax-parse-rule (log-resyntax-rule-condition expr:expr)
+  #:with line (syntax-line (attribute expr))
+  (log-resyntax-rule-condition-impl expr #:line 'line #:datum 'expr))