Refactor read-and-parse.scm

2 files changed, 7 insertions, 5 deletions

diff --git a/compiler/main.scm b/compiler/main.scm
index 97e4638..44d7ac5 100644
--- a/compiler/main.scm
+++ b/compiler/main.scm
@@ -24,7 +24,6 @@
   #:use-module (compiler passes preprocess-policy)
   #:use-module (compiler passes read-and-parse)
   #:use-module (compiler utilities)
-  #:use-module (ice-9 pretty-print)
   #:use-module (srfi srfi-1)
   #:use-module (srfi srfi-11)
   #:export (main))
diff --git a/compiler/passes/read-and-parse.scm b/compiler/passes/read-and-parse.scm
index ec36c74..2f2c8c2 100644
--- a/compiler/passes/read-and-parse.scm
+++ b/compiler/passes/read-and-parse.scm
@@ -23,10 +23,11 @@
   #:export (read-and-parse))
 
 (define (call-command-with-output-error-to-string cmd)
-  "Invoke `cmd', recording what it writes to `stdout' and `stderr'
+  "Invoke CMD, recording what it writes to `stdout' and `stderr'
 
-Multi-valued return. The first value is a string containing the content of
-`stdout', and the second value is a string containing the content of `stderr'."
+Multi-valued return. The first value is a string or `eof-object?'
+containing the content of `stdout', and the second value is a string or
+`eof-object?' containing the content of `stderr'."
   (let* ((err-cons (pipe))
          (port (with-error-to-port (cdr err-cons)
                  (λ() (open-input-pipe cmd))))
@@ -39,12 +40,14 @@ Multi-valued return. The first value is a string containing the content of
      (read-delimited "" (car err-cons)))))
 
 (define (read-and-parse file-name)
-  "Pass to read the contents of `file-name' and output an AST"
+  "Pass to read the contents of FILE-NAME and output a syntax tree"
   (define-values (stdout stderr)
     (call-command-with-output-error-to-string
      (string-concatenate (list "opa parse -f json " file-name))))
 
   ;; Fail if anything was written to stdout.
+  (unless (eof-object? stderr)
+    (display stderr))
   (assert (eof-object? stderr))
 
   (json-string->scm stdout))