" File: explainpat.vim
" Created: 2011 Nov 02
-" Last Change: 2012 Dec 19
-" Rev Days: 3
+" Last Change: 2013 Mar 09
+" Rev Days: 8
" Author: Andy Wokula <anwoku@yahoo.de>
" License: Vim License, see :h license
-" Version: 0.2
+" Version: 0.5
" Implements :ExplainPattern [pattern]
" TODO {{{
" - more testing, completeness check
-" - detailed collections
-" - \z
+" ? detailed collections
" ? literal string: also print the unescaped magic items
" ? literal string: show leading/trailing spaces
-" + start of "first" capturing group, start of 2nd ...
-" + `\|' should get less indent than the branches, do we need to create an
-" AST? ! no, keep it straight forward
-" + \%[...]
-" + \{, \{-
+"
"}}}
" Init Folklore {{{
let g:explainpat#loaded = 1
"}}}
-func! explainpat#ExplainPattern(cmd_arg) "{{{
+func! explainpat#ExplainPattern(cmd_arg, ...) "{{{
+ " {a:1} alternative help printer object (caution, no sanity check)
+ " (for test running)
if a:cmd_arg == ""
" let pattern_str = nwo#vis#Get()
echo "(usage) :ExplainPattern [{register} | {pattern}]"
echo printf('Magic Pattern: %s', magicpat)
endif
- " hmm, we need state for \%[ ... ]
+ " we need state:
+ " set flag when in `\%[ ... ]' (optionally matched atoms):
let s:in_opt_atoms = 0
+ " counter for `\(':
let s:capture_group_nr = 0
+ " >=1 at pos 0 or after '\|', '\&', '\(', '\%(' or '\n'; else 0 or less:
+ let s:at_begin_of_pat = 1
- let hulit = s:NewHelpPrinter()
+ let hulit = a:0>=1 && type(a:1)==s:DICT ? a:1 : s:NewHelpPrinter()
call hulit.AddIndent(' ')
let bull = s:NewTokenBiter(magicpat, '')
while !bull.AtEnd()
call hulit.Print(item, Doc)
elseif type(Doc) == s:FUNCREF
call call(Doc, [bull, hulit, item])
+ elseif type(Doc) == s:LIST
+ call call(Doc[0], [bull, hulit, item, Doc[1]])
endif
+ let s:at_begin_of_pat -= 1
else
echoerr printf('ExplainPattern: cannot parse "%s"', bull.Rest())
break
let s:STRING = type("")
let s:DICT = type({})
let s:FUNCREF = type(function("tr"))
+let s:LIST = type([])
" }}}
-let s:magic_item_pattern = '\C^\%(\\\%(@<.\|%[dxouU[(^$V#<>]\=\|z[1-9se(]\|{\|@[>=!]\|_[[^$.]\=\|.\)\|.\)'
+let s:magic_item_pattern = '\C^\%(\\\%(@<.\|%[dxouU[(^$V#<>]\=\|z[1-9se(]\|@[>=!]\|_[[^$.]\=\|.\)\|.\)'
let s:doc = {} " {{{
" this is all the help data ...
func! s:DocOrBranch(bull, hulit, item) "{{{
call a:hulit.RemIndent()
- call a:hulit.Print(a:item, "OR branch")
+ call a:hulit.Print(a:item, "OR (separate alternatives)")
call a:hulit.AddIndent(' ')
+ let s:at_begin_of_pat = 2
endfunc "}}}
let s:doc['\|'] = function("s:DocOrBranch")
-let s:doc['\&'] = "AND branch"
+
+func! s:DocBeginOfPat(bull, hulit, item, msg) "{{{
+ call a:hulit.Print(a:item, a:msg)
+ let s:at_begin_of_pat = 2
+endfunc "}}}
+
+let s:doc['\&'] = [function("s:DocBeginOfPat"), "AND (separate concats, all must match)"]
let s:ord = split('n first second third fourth fifth sixth seventh eighth ninth')
func! s:DocGroupStart(bull, hulit, item) "{{{
if a:item == '\%('
call a:hulit.Print(a:item, "start of non-capturing group")
- else " a:item == '\('
+ elseif a:item == '\('
let s:capture_group_nr += 1
call a:hulit.Print(a:item, printf("start of %s capturing group", get(s:ord, s:capture_group_nr, '(invalid)')))
+ else " a:item == '\z('
+ call a:hulit.Print(a:item, 'start of "external" group (only usable in :syn-region)')
endif
call a:hulit.AddIndent('| ', ' ')
+ let s:at_begin_of_pat = 2
endfunc "}}}
func! s:DocGroupEnd(bull, hulit, item) "{{{
call a:hulit.RemIndent(2)
let s:doc['\('] = function("s:DocGroupStart")
let s:doc['\%('] = function("s:DocGroupStart")
let s:doc['\)'] = function("s:DocGroupEnd")
+" let s:doc['\z('] = "only in syntax scripts"
+let s:doc['\z('] = function("s:DocGroupStart")
+
+func! s:DocStar(bull, hulit, item) "{{{
+ if s:at_begin_of_pat >= 1
+ " call a:hulit.Print(a:item, "(at begin of pattern) literal `*'")
+ call a:hulit.AddLiteral(a:item)
+ else
+ call a:hulit.Print(a:item, "(multi) zero or more of the preceding atom")
+ endif
+endfunc "}}}
+
+" let s:doc['*'] = "(multi) zero or more of the preceding atom"
+let s:doc['*'] = function("s:DocStar")
-let s:doc['\z('] = "only in syntax scripts"
-let s:doc['*'] = "(multi) zero or more of the preceding atom"
let s:doc['\+'] = "(multi) one or more of the preceding atom"
let s:doc['\='] = "(multi) zero or one of the preceding atom"
let s:doc['\?'] = "(multi) zero or one of the preceding atom"
let s:doc['\@!'] = "(assertion) forbid match for preceding atom"
let s:doc['\@<='] = "(assertion) require match for preceding atom to the left"
let s:doc['\@<!'] = "(assertion) forbid match for preceding atom to the left"
-let s:doc['^'] = "(assertion) require match at start of line"
+
+func! s:DocCircumFlex(bull, hulit, item) "{{{
+ if s:at_begin_of_pat >= 1
+ call a:hulit.Print(a:item, "(assertion) require match at start of line")
+ " after `^' is not at begin of pattern ... handle special case `^*' here:
+ if a:bull.Bite('^\*') == "*"
+ call a:hulit.AddLiteral("*")
+ endif
+ else
+ " call a:hulit.Print(a:item, "(not at begin of pattern) literal `^'")
+ call a:hulit.AddLiteral(a:item)
+ endif
+endfunc "}}}
+
+" let s:doc['^'] = "(assertion) require match at start of line"
+let s:doc['^'] = function("s:DocCircumFlex")
+
let s:doc['\_^'] = "(assertion) like `^', allowed anywhere in the pattern"
-let s:doc['$'] = "(assertion) require match at end of line"
+
+func! s:DocDollar(bull, hulit, item) "{{{
+ if a:bull.Rest() =~ '^$\|^\\[&|)n]'
+ call a:hulit.Print(a:item, "(assertion) require match at end of line")
+ else
+ call a:hulit.AddLiteral(a:item)
+ endif
+endfunc "}}}
+
+" let s:doc['$'] = "(assertion) require match at end of line"
+let s:doc['$'] = function("s:DocDollar")
+
let s:doc['\_$'] = "(assertion) like `$', allowed anywhere in the pattern"
let s:doc['.'] = "match any character"
let s:doc['\_.'] = "match any character or newline"
let s:doc['\t'] = "match <Tab>"
let s:doc['\r'] = "match <CR>"
let s:doc['\b'] = "match CTRL-H"
-let s:doc['\n'] = "match a newline"
+let s:doc['\n'] = [function("s:DocBeginOfPat"), "match a newline"]
let s:doc['~'] = "match the last given substitute string"
let s:doc['\1'] = "match first captured string"
let s:doc['\2'] = "match second captured string"
let s:doc['\8'] = "match eighth captured string"
let s:doc['\9'] = "match ninth captured string"
-" \z1
-" \z2
-" \z9
+let s:doc['\z1'] = 'match same string matched by first "external" group'
+let s:doc['\z2'] = 'match same string matched by second "external" group'
+let s:doc['\z3'] = 'match same string matched by third "external" group'
+let s:doc['\z4'] = 'match same string matched by fourth "external" group '
+let s:doc['\z5'] = 'match same string matched by fifth "external" group'
+let s:doc['\z6'] = 'match same string matched by sixth "external" group'
+let s:doc['\z7'] = 'match same string matched by seventh "external" group'
+let s:doc['\z8'] = 'match same string matched by eighth "external" group'
+let s:doc['\z9'] = 'match same string matched by ninth "external" group'
" from MakeMagic()
" skip the rest of a collection
-let s:coll_skip_pat = '^\^\=]\=\%(\%(\\[\^\]\-\\bertn]\|\[:\w\+:]\|[^\]]\)\@>\)*]'
+let s:coll_skip_pat = '^\^\=]\=\%(\%(\\[\^\]\-\\bertn]\|\[:\w\+:]\|\[=.=]\|\[\..\.]\|[^\]]\)\@>\)*]'
func! s:DocCollection(bull, hulit, item) "{{{
let collstr = a:bull.Bite(s:coll_skip_pat)
- let inverse = collstr =~ '^\^'
- let with_nl = a:item == '\_['
- let descr = inverse ? printf('collection not matching [%s', collstr[1:]) : 'collection'
- let descr_nl = printf("%s%s", (inverse && with_nl ? ', but' : ''), (with_nl ? ' with end-of-line added' : ''))
- call a:hulit.Print(a:item. collstr, descr. descr_nl)
+ if collstr != ""
+ let inverse = collstr =~ '^\^'
+ let with_nl = a:item == '\_['
+ let descr = inverse ? printf('collection not matching [%s', collstr[1:]) : 'collection'
+ let descr_nl = printf("%s%s", (inverse && with_nl ? ', but' : ''), (with_nl ? ' with end-of-line added' : ''))
+ call a:hulit.Print(a:item. collstr, descr. descr_nl)
+ else
+ call a:hulit.AddLiteral('[')
+ endif
endfunc "}}}
let s:doc['['] = function("s:DocCollection")
let s:doc['\%['] = function("s:DocOptAtoms")
let s:doc[']'] = function("s:DocOptAtoms")
-let s:doc['\c'] = "ignore case while matching the pattern"
-let s:doc['\C'] = "match case while matching the pattern"
-let s:doc['\Z'] = "ignore composing characters in the pattern"
+func! s:DocAnywhere(bull, hulit, item, msg) "{{{
+ call a:hulit.Print(a:item, a:msg)
+ " keep state:
+ let s:at_begin_of_pat += 1
+endfunc "}}}
+
+let s:doc['\c'] = [function("s:DocAnywhere"), "ignore case while matching the pattern"]
+let s:doc['\C'] = [function("s:DocAnywhere"), "match case while matching the pattern"]
+let s:doc['\Z'] = [function("s:DocAnywhere"), "ignore composing characters in the pattern"]
" \%d 123
" \%x 2a
return bite
endfunc "}}}
- " get the unparsed rest of input
+ " get the unparsed rest of input (not consuming)
func! obj.Rest() "{{{
return self.str
endfunc "}}}