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Diffstat (limited to 'ipl/procs/stripunb.icn')
| -rw-r--r-- | ipl/procs/stripunb.icn | 134 |
1 files changed, 134 insertions, 0 deletions
diff --git a/ipl/procs/stripunb.icn b/ipl/procs/stripunb.icn new file mode 100644 index 0000000..21fe89a --- /dev/null +++ b/ipl/procs/stripunb.icn @@ -0,0 +1,134 @@ +############################################################################ +# +# File: stripunb.icn +# +# Subject: Procedures to strip unbalanced material +# +# Author: Richard L. Goerwitz +# +# Date: May 2, 2001 +# +############################################################################ +# +# This file is in the public domain. +# +############################################################################ +# +# Version: 1.7 +# +############################################################################ +# +# This routine strips material from a line which is unbalanced with +# respect to the characters defined in arguments 1 and 2 (unbalanced +# being defined as bal() defines it, except that characters preceded +# by a backslash are counted as regular characters, and are not taken +# into account by the balancing algorithm). +# +# One little bit of weirdness I added in is a table argument. Put +# simply, if you call stripunb() as follows, +# +# stripunb('<','>',s,&null,&null,t) +# +# and if t is a table having the form, +# +# key: "bold" value: outstr("\e[2m", "\e1m") +# key: "underline" value: outstr("\e[4m", "\e1m") +# etc. +# +# then every instance of "<bold>" in string s will be mapped to +# "\e2m," and every instance of "</bold>" will be mapped to "\e[1m." +# Values in table t must be records of type output(on, off). When +# "</>" is encountered, stripunb will output the .off value for the +# preceding .on string encountered. +# +############################################################################ +# +# Links: scan +# +############################################################################ + +link scan + +global last_k +record outstr(on, off) + + +procedure stripunb(c1,c2,s,i,j,t) + + # NB: Stripunb() returns a string - not an integer (like find, + # upto). + + local lookinfor, bothcs, s2, k, new_s, c, compl + #global last_k + initial last_k := list() + + /c1 := '<' + /c2 := '>' + bothcs := c1 ++ c2 + lookinfor := c1 ++ '\\' + c := &cset -- c1 -- c2 + + /s := &subject + if \i then { + if i < 1 then + i := *s + (i+1) + } + else i := \&pos | 1 + if \j then { + if j < 1 then + j := *s + (j+1) + } + else j := *s + 1 + + s2 := "" + s ? { + while s2 ||:= tab(upto(lookinfor)) do { + if ="\\" then { + if not any(bothcs) then + s2 ||:= "\\" + &pos+1 > j & (return s2) + s2 ||:= move(1) + next + } + else { + &pos > j & (return s2) + any(c1) | + stop("stripunb: Unbalanced string, pos(",&pos,").\n",s) + if not (k := tab(&pos <= slashbal(c,c1,c2,&subject))) + then { + # If the last char on the line is the right-delim... + if (.&subject[&pos:0]||" ") ? slashbal(c,c1,c2) + # ...then, naturally, the rest of the line is the tag. + then k := tab(0) + else { + # BUT, if it's not the right-delim, then we have a + # tag split by a line break. Blasted things. + return stripunb(c1,c2,&subject||read(&input), + *.&subject,,t) | + # Can't find the right delimiter. Parsing error. + stop("stripunb: Incomplete tag\n",s[1:80] | s) + } + } + # T is the maptable. + if \t then { + k ?:= 2(tab(any(c1)), tab(upto(c2)), move(1), pos(0)) + if k ?:= (="/", tab(0)) then { + compl:= pop(last_k) | stop("Incomplete tag, ",&subject) + if k == "" + then k := compl + else k == compl | stop("Incorrectly paired tag,/tag.") + s2 ||:= \(\t[k]).off + } + else { + s2 ||:= \(\t[k]).on + push(last_k, k) + } + } + } + } + s2 ||:= tab(0) + } + + return s2 + +end |