diff options
| -rw-r--r-- | shell/parse.mu | 39 |
1 files changed, 25 insertions, 14 deletions
diff --git a/shell/parse.mu b/shell/parse.mu index 530f13b4..357b48fb 100644 --- a/shell/parse.mu +++ b/shell/parse.mu @@ -7,7 +7,9 @@ fn parse-input tokens: (addr stream cell), out: (addr handle cell), trace: (addr error trace, "nothing to parse" return } - var close-paren?/eax: boolean <- parse-sexpression tokens, out, trace + var close-paren?/eax: boolean <- copy 0/false + var dummy?/ecx: boolean <- copy 0/false + close-paren?, dummy? <- parse-sexpression tokens, out, trace { compare close-paren?, 0/false break-if-= @@ -22,8 +24,10 @@ fn parse-input tokens: (addr stream cell), out: (addr handle cell), trace: (addr } } -# return value: true if close-paren was encountered -fn parse-sexpression tokens: (addr stream cell), _out: (addr handle cell), trace: (addr trace) -> _/eax: boolean { +# return values: +# unmatched close-paren encountered? +# dot encountered? (only used internally by recursive calls) +fn parse-sexpression tokens: (addr stream cell), _out: (addr handle cell), trace: (addr trace) -> _/eax: boolean, _/ecx: boolean { trace-text trace, "read", "parse" trace-lower trace var curr-token-storage: cell @@ -33,7 +37,7 @@ fn parse-sexpression tokens: (addr stream cell), _out: (addr handle cell), trace { break-if-= error trace, "end of stream; never found a balancing ')'" - return 1/true + return 1/true, 0/false } read-from-stream tokens, curr-token $parse-sexpression:type-check: { @@ -45,11 +49,13 @@ fn parse-sexpression tokens: (addr stream cell), _out: (addr handle cell), trace var out/edi: (addr handle cell) <- copy _out allocate-pair out var out-addr/eax: (addr cell) <- lookup *out - var left-ah/ecx: (addr handle cell) <- get out-addr, left + var left-ah/edx: (addr handle cell) <- get out-addr, left new-symbol left-ah, "'" - var right-ah/ecx: (addr handle cell) <- get out-addr, right - var result/eax: boolean <- parse-sexpression tokens, right-ah, trace - return result + var right-ah/edx: (addr handle cell) <- get out-addr, right + var close-paren?/eax: boolean <- copy 0/false + var dot?/ecx: boolean <- copy 0/false + close-paren?, dot? <- parse-sexpression tokens, right-ah, trace + return close-paren?, dot? } # not bracket -> parse atom var bracket-token?/eax: boolean <- bracket-token? curr-token @@ -67,9 +73,11 @@ fn parse-sexpression tokens: (addr stream cell), _out: (addr handle cell), trace var curr/esi: (addr handle cell) <- copy _out allocate-pair curr var curr-addr/eax: (addr cell) <- lookup *curr - var left/ecx: (addr handle cell) <- get curr-addr, left + var left/edx: (addr handle cell) <- get curr-addr, left { - var close-paren?/eax: boolean <- parse-sexpression tokens, left, trace + var close-paren?/eax: boolean <- copy 0/false + var dot?/ecx: boolean <- copy 0/false + close-paren?, dot? <- parse-sexpression tokens, left, trace compare close-paren?, 0/false break-if-!= var curr-addr/eax: (addr cell) <- lookup *curr @@ -77,8 +85,11 @@ fn parse-sexpression tokens: (addr stream cell), _out: (addr handle cell), trace var tmp-storage: (handle cell) var tmp/edx: (addr handle cell) <- address tmp-storage $parse-sexpression:list-loop: { - var close-paren?/eax: boolean <- parse-sexpression tokens, tmp, trace + var close-paren?/eax: boolean <- copy 0/false + var dot?/ecx: boolean <- copy 0/false + close-paren?, dot? <- parse-sexpression tokens, tmp, trace allocate-pair curr + # ')' -> return compare close-paren?, 0/false break-if-!= var curr-addr/eax: (addr cell) <- lookup *curr @@ -91,13 +102,13 @@ fn parse-sexpression tokens: (addr stream cell), _out: (addr handle cell), trace } break $parse-sexpression:type-check } - # close paren -> parse list + # close paren -> return var close-paren?/eax: boolean <- close-paren-token? curr-token compare close-paren?, 0/false { break-if-= trace-higher trace - return 1/true + return 1/true, 0/false } # otherwise abort var stream-storage: (stream byte 0x40) @@ -110,7 +121,7 @@ fn parse-sexpression tokens: (addr stream cell), _out: (addr handle cell), trace trace trace, "error", stream } trace-higher trace - return 0/false + return 0/false, 0/false } fn parse-atom _curr-token: (addr cell), _out: (addr handle cell), trace: (addr trace) { |