From aa3a57d293ce702db333a322ca3676862846b602 Mon Sep 17 00:00:00 2001
From: Christophe Rhodes <csr21@cantab.net>
Date: Thu, 9 Sep 2010 10:38:53 +0100
Subject: [PATCH] the beginnings of an inspector

Implement enough that C-c I begins to work, at least for values like
list(1,2,3).  The resulting inspector on the emacs side apparently has
no features, and an error message results on quitting the inspector
because I've only implemented `swank:init-inspector`, and not
`swank:quit-inspector`.  Still, good enough to checkpoint.
---
 swank.R | 76 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 76 insertions(+)

diff --git a/swank.R b/swank.R
index 22dd532..2d2bf77 100644
--- a/swank.R
+++ b/swank.R
@@ -460,3 +460,79 @@ withRetryRestart <- function(description, expr) {
   eval(parse(text=sprintf("%s <- %s", string, value)), envir = globalenv())
   TRUE
 }
+
+resetInspector <- function(slimeConnection) {
+  assign("istate", list(), envir=slimeConnection)
+  assign("inspectorHistory", NULL, envir=slimeConnection)
+}
+
+`swank:init-inspector` <- function(slimeConnection, sldbState, string) {
+  withRetryRestart("retry SLIME inspection request",
+                   { resetInspector(slimeConnection)
+                     value <- inspectObject(slimeConnection, eval(parse(text=string), envir=globalenv()))
+                   })
+  value
+}
+
+inspectObject <- function(slimeConnection, object) {
+  slimeConnection$istate <- list(object=object, previous=slimeConnection$istate)
+  slimeConnection$istate$content <- emacsInspect(object)
+  if(!object %in% slimeConnection$inspectorHistory) {
+    slimeConnection$inspectorHistory <- c(slimeConnection$inspectorHistory, object)
+  }
+  if(!is.null(slimeConnection$istate$previous)) {
+    slimeConnection$istate$previous$`next` <- slimeConnection$istate
+  }
+  istateToElisp(slimeConnection$istate)
+}
+
+valuePart <- function(istate, object, string) {
+  list(quote(`:value`),
+       if(is.null(string)) printToString(object) else string,
+       assignIndexInParts(object, istate))
+}
+
+preparePart <- function(istate, part) {
+  if(is.character(part)) {
+    list(part)
+  } else {
+    switch(as.character(part[[1]]),
+           `:newline` = list("\n"),
+           `:value` = valuePart(istate, part[[2]], part[[3]]),
+           `:line` = list(printToString(part[[2]]), ": ",
+             valuePart(istate, part[[3]], NULL), "\n"))
+  }
+}
+
+prepareRange <- function(istate, start, end) {
+  range <- istate$content[start+1:min(end+1, length(istate$content))]
+  ps <- NULL
+  for(part in range) {
+    ps <- c(ps, preparePart(istate, part))
+  }
+  list(ps, if(length(ps)<end-start) { start+length(ps) } else { end+1000 },
+       start, end)
+}
+
+assignIndexInParts <- function(object, istate) {
+  ret <- 1+length(istate$parts)
+  istate$parts <- c(istate$parts, object)
+  ret
+}
+
+istateToElisp <- function(istate) {
+  list(quote(`:title`), deparse(istate$object, control="all", nlines=1),
+       quote(`:id`), assignIndexInParts(istate$object, istate),
+       quote(`:content`), prepareRange(istate, 0, 500))
+}
+
+emacsInspect <- function(object) {
+  UseMethod("emacsInspect")
+}
+
+emacsInspect.list <- function(list) {
+  c(list("a list", list(quote(`:newline`))),
+    mapply(function(name, value) { list(list(quote(`:line`), name, value)) },
+           names(list), list))
+}
+
-- 
2.30.2