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Diffstat (limited to 'miralib/prelude')
| -rw-r--r-- | miralib/prelude | 110 |
1 files changed, 110 insertions, 0 deletions
diff --git a/miralib/prelude b/miralib/prelude new file mode 100644 index 0000000..f9fe7a7 --- /dev/null +++ b/miralib/prelude @@ -0,0 +1,110 @@ +||names defined in this file are not in scope for users - they are part +||of the internal mechanisms of the Miranda system. + +||the following three identifiers are "untypeable" and defined internally +||changetype::*->** ||primitive function, semantically equivalent to id +||first::*->** ||gets first element of a tuple +||rest::*->** ||gets rest of a tuple (i.e. without first component) + +||offside::[char] ||defined internally and used by indent, see below + + diagonalise :: [[*]]->[*] ||used by [//] comprehensions + diagonalise x = diag 1 x ||when nested does "cantorian" diagonalisation + diag n [] = [] + diag n x = map hd px++diag (#px+1)rest, otherwise + where + px = filter (~=[]) (take n x) + rest = map tl px ++ drop n x + listdiff::[*]->[*]->[*] ||listdiff defines the action of "--" + listdiff x [] = x + listdiff x (b:y) = listdiff (remove b x) y + remove b [] = [] + remove b (a:x) = x, if a=b + = a:remove b x, otherwise + showbool::bool->[char] + showbool True = "True" + showbool False = "False" +||shownum defined internally + base r x = "0", if x=0 ||base is used by charname + = f x, otherwise + where + f 0 = [] + f n = f(n div r) ++ [mkdigit(n mod r)] + mkdigit n = decode(n + code '0'), if n<10 + = decode(n - 10 + code 'a'), if 10<=n<36 + showchar::char->[char] + showchar x = "'" ++ charname x ++ "'" +||note - charname has the right conventions for showchar +||i.e. ' is escaped and " is not escaped - showstring inverts this + charname '\\' = "\\\\" + charname '\'' = "\\\'" + charname x = [x], if 32 <= code x < 127 \/ 160 <= code x < 256 + charname '\a' = "\\a" + charname '\b' = "\\b" + charname '\f' = "\\f" + charname '\n' = "\\n" + charname '\r' = "\\r" + charname '\t' = "\\t" + charname '\v' = "\\v" + charname x = "\\" ++ pad 3 (base 10 n), if n<1000 ||H=this case only & no pad + = "\\x" ++ pad 4 (base 16 n), if n<=0xffff + = "\\X" ++ pad 6 (base 16 n), otherwise + where + n = code x + pad w s = rep(w-#s)'0'++s + rep n x = [], if n<=0 + = x:rep (n-1) x, otherwise + showlist::(*->[char])->[*]->[char] + showlist f x = '[':rest + where + rest = "]", if x=[] + = f(hd x)++foldr g "]" (tl x), otherwise + g a s = ',':f a++s + showstring::[char]->[char] + showstring x = '"' : showstr x + showstr [] = "\"" + showstr ('"':x) = "\\\"" ++ showstr x + showstr (a:x) = s ++ showstr x ||for Haskell style padding use s1 here + where ||see also line marked H above + s = charname a +|| s1 = s ++ "\\&", if clash s x +|| = s, otherwise +|| clash ('\\':c:cs) (d:ds) = digit c & digit d +|| clash s x = False + digit c = '0' <= c <= '9' + shownum1::num->[char] + shownum1 n = "("++shownum n++")", if n<0 + = shownum n, otherwise + showparen::(*->[char])->*->[char] + showparen f x = "("++f x++")" + showpair::(*->[char])->(**->[char])->***->[char] + showpair f1 f2 tup = f1(first tup)++","++f2(rest tup) + showvoid::()->[char] + showvoid () = "()" + showfunction::(*->**)->[char] + showfunction x = "<function>" + showabstract::*->[char] + showabstract x = "<abstract ob>" + showwhat::*->[char] + showwhat x = error "undeclared show-function", if x=x +||the following function is used to implement the offside rule (under %bnf) + indent :: *->**->** || * is type of `col' function, ** is parser + outdent :: *->* || * is a parser + indent = changetype indent1 + outdent = changetype outdent1 + indent1 col f ((a,s):x) + = f ((a,s):cutoff col (col s) x), if a~=offside + indent1 col f x = f x + cutoff col n = g + where + g ((a,s):x) = (a,s):g x, if col s>=n + = (offside,s):(a,s):x, otherwise + g [] = [] + outdent1 f = reconstruct.f + reconstruct (m:x) = m:g x + where + g ((a,s):x) = x, if a=offside + g (t:x) = t:g x + g [] = [] + reconstruct fail = fail ||internal repn of failure is a non-CONS object +||offside is defined internally and differs from every string |