1:- module(onepointfour_basics_stringy_justify, 2 [ 3 justify_left/4 % justify_left(FieldWidth,Text,Result,ResultType) 4 ,justify_left/5 % justify_left(FieldWidth,Text,Result,ResultType,SettingsDict) 5 ,justify_right/4 % justify_right(FieldWidth,Text,Result,ResultType) 6 ,justify_right/5 % justify_right(FieldWidth,Text,Result,ResultType,SettingsDict) 7 ,justify_center/4 % justify_center(FieldWidth,Text,Result,ResultType) 8 ,justify_center/5 % justify_center(FieldWidth,Text,Result,ResultType,SettingsDict) 9 ,justify_how/5 % justify_how(How,FieldWidth,Text,Result,ResultType) 10 ,justify_how/6 % justify_how(How,FieldWidth,Text,Result,ResultType,SettingsDict) 11 ]). 12 13:- use_module(library('onepointfour_basics/stringy_overwrite.pl')). 14:- use_module(library('onepointfour_basics/dict_settings.pl')). 15:- use_module(library('onepointfour_basics/checks.pl')). 16:- use_module(library('onepointfour_basics/stringy_length.pl')). 17:- use_module(library('onepointfour_basics/space_stringy.pl')). 18 19/* MIT License Follows (https://opensource.org/licenses/MIT) 20 21 Copyright 2021 David Tonhofer <ronerycoder@gluino.name> 22 23 Permission is hereby granted, free of charge, to any person obtaining 24 a copy of this software and associated documentation files 25 (the "Software"), to deal in the Software without restriction, 26 including without limitation the rights to use, copy, modify, merge, 27 publish, distribute, sublicense, and/or sell copies of the Software, 28 and to permit persons to whom the Software is furnished to do so, 29 subject to the following conditions: 30 31 The above copyright notice and this permission notice shall be 32 included in all copies or substantial portions of the Software. 33 34 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 35 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 36 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. 37 IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY 38 CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, 39 TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE 40 SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 41*/ 42 43/* pldoc ==================================================================== */
57justify_how(How,FieldWidth,Text,Result,ResultType) :-
58 justify_how(How,FieldWidth,Text,Result,ResultType,_{}).cut_left - a boolean, cut the result at left field limit (default true) cut_right - a boolean, cut the result at right field limit (default true) offset - an integer, used for "offset on the left" when justifying left
68justify_how(How,FieldWidth,Text,Result,ResultType,SettingsDict) :- 69 assertion(check_that(How,[hard(member(left,right,center))])), 70 ( 71 (How==left) 72 -> 73 justify_left(FieldWidth,Text,Result,ResultType,SettingsDict) 74 ; 75 (How==right) 76 -> 77 justify_right(FieldWidth,Text,Result,ResultType,SettingsDict) 78 ; 79 (How==center) 80 -> 81 justify_center(FieldWidth,Text,Result,ResultType,SettingsDict) 82 ). 83 84% ----------------------------------------------------------------------------------- 85 86/* Justify left 87 88 case of positive offset 89 90 |************************FieldWidth****************************| 91 |**Offset**|******TextWidth*********|---------PadWidth---------| 92 |~~~~~~~~~ReducedFieldWidth~~~~~~~~~| 93 94 case of positive offset with negative PadWidth 95 96 |************************FieldWidth****************************| 97 |**Offset**|***********************TextWidth*********************************| 98 |~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ReducedFieldWidth~~~~~~~~~~~~~~~~~~~~~~~~~~~~~| 99 |--PadWidth---| 100 101 case of negative offset with positive PadWdith 102 103 |************************FieldWidth****************************| 104 |**Offset**|******TextWidth*********|-----------------PadWidth------------| 105 |~~~~~~~~~ReducedFieldWidth~~~~~~~~~| 106 107*/
113justify_left(FieldWidth,Text,Result,ResultType) :-
114 justify_left(FieldWidth,Text,Result,ResultType,_{}).string, atom).
ResultType can also be deduced if Result is instantiated on call,
or else from the given Text.
SettingsDict can contain:
cut_left - a boolean, cut the result at left field limit (default true) cut_right - a boolean, cut the result at right field limit (default true) offset - an integer, used for "offset on the left" when justifying left
129justify_left(FieldWidth,Text,Result,ResultType,SettingsDict) :- 130 decaps_cut_flags(SettingsDict,CutLeft,CutRight), 131 decaps_offset(SettingsDict,Offset), 132 common_entry_checks(FieldWidth,Text,Result,ResultType), 133 complete_result_type(Text,Result,ResultType), 134 space_stringy(FieldWidth,BgText,string), 135 stringy_overwrite(BgText,Text,Offset,CutLeft,CutRight,Result,ResultType). 136 137% ----------------------------------------------------------------------------------- 138 139/* Justify right 140 141 case of positive offset 142 143 |************************FieldWidth****************************| 144 |-------PadWidth-----------|*********TextWidth******|**Offset**| 145 146 case of negative offset 147 148 |************************FieldWidth****************************| 149 |---------------------PadWidth----------------------|*********TextWidth******| 150 |***Offset****| 151*/
157justify_right(FieldWidth,Text,Result,ResultType) :-
158 justify_right(FieldWidth,Text,Result,ResultType,_{}).string, atom).
ResultType can also be deduced if Result is instantiated on call,
or else from the given Text.
SettingsDict can contain:
cut_left cut_right offset
173justify_right(FieldWidth,Text,Result,ResultType,SettingsDict) :- 174 decaps_cut_flags(SettingsDict,CutLeft,CutRight), 175 decaps_offset(SettingsDict,Offset), 176 common_entry_checks(FieldWidth,Text,Result,ResultType), 177 complete_result_type(Text,Result,ResultType), 178 stringy_length(Text,TextWidth), 179 PadWidth is FieldWidth-TextWidth-Offset, 180 space_stringy(FieldWidth,BgText,string), 181 stringy_overwrite(BgText,Text,PadWidth,CutLeft,CutRight,Result,ResultType). 182 183% ----------------------------------------------------------------------------------- 184 185/* Justify center 186 187 case of positive offset 188 189 |********************************************FieldWidth***********************************************| 190 |**OffsetLeft**|---PadLeftWidth---|**********TextWidth*********|----PadRightWidth-----|**OffsetRight**| 191 |~~~~~~~~~~~~~~~~~~~~~~~~ReducedFieldWidth~~~~~~~~~~~~~~~~~~~~~~~~~~~~~| 192 193*/
199justify_center(FieldWidth,Text,Result,ResultType) :-
200 justify_center(FieldWidth,Text,Result,ResultType,_{}).string, atom).
ResultType can also be deduced if Result is instantiated on call,
or else from the given Text.
SettingsDict can contain:
218justify_center(FieldWidth,Text,Result,ResultType,SettingsDict) :- 219 decaps_offset_left_right(SettingsDict,OffsetLeft,OffsetRight), 220 decaps_cut_flags(SettingsDict,CutLeft,CutRight), 221 decaps_prefer(SettingsDict,Prefer), 222 common_entry_checks(FieldWidth,Text,Result,ResultType), 223 complete_result_type(Text,Result,ResultType), 224 stringy_length(Text,TextWidth), 225 ReducedFieldWidth is FieldWidth-OffsetLeft-OffsetRight, % could already be negative 226 ((ReducedFieldWidth < 0) 227 -> 228 deal_with_negative_reduced_field_width(ReducedFieldWidth,FieldWidth,OffsetLeft,OffsetRight,Text,Result,ResultType,CutLeft,CutRight,Prefer) 229 ; 230 deal_with_pos0_reduced_field_width(ReducedFieldWidth,FieldWidth,OffsetLeft,Text,TextWidth,Result,ResultType,CutLeft,CutRight,Prefer)). 231 232deal_with_negative_reduced_field_width(ReducedFieldWidth,FieldWidth,OffsetLeft,OffsetRight,Text,Result,ResultType,CutLeft,CutRight,Prefer) :- 233 Half is (-ReducedFieldWidth)//2, % round towards 0 (in principle) 234 OtherHalf is (-ReducedFieldWidth) - Half, 235 NewOffsetLeft is OffsetLeft - Half, 236 NewOffsetRight is OffsetRight - OtherHalf, 237 assertion(FieldWidth =:= NewOffsetLeft+NewOffsetRight), 238 % calls itself now 239 justify_center(FieldWidth,Text,Result,ResultType, 240 _{offset_left : NewOffsetLeft, 241 offset_right : NewOffsetRight, 242 cut_left : CutLeft, 243 cut_right : CutRight, 244 prefer : Prefer}). 245 246deal_with_pos0_reduced_field_width(ReducedFieldWidth,FieldWidth,OffsetLeft,Text,TextWidth,Result,ResultType,CutLeft,CutRight,Prefer) :- 247 odd_even(ReducedFieldWidth,TaggedReducedFieldWidth), 248 odd_even(TextWidth,TaggedTextWidth), 249 once(start_pos(TaggedReducedFieldWidth,TaggedTextWidth,Prefer,StartPos)), 250 AbsoluteStartPos is OffsetLeft + StartPos, 251 space_stringy(FieldWidth,BgText,string), 252 stringy_overwrite(BgText,Text,AbsoluteStartPos,CutLeft,CutRight,Result,ResultType). 253 254% ----------------------------------------------------------------------------------- 255 256odd_even(X,odd(X)) :- (X mod 2) =:= 1, !. 257odd_even(X,even(X)). 258 259% In two cases the StartPosition is computed as ReducedFieldWidth//2 - TextWidth//2 260% 261% oooooooooXiiiiiiiii ReducedFieldWidth is odd (and has a central character) 262% aaaXbbb TextWidth is odd (and has a central character) 263% 264% or 265% 266% ooooooooooiiiiiiiiii ReducedFieldWidth is even 267% aaabbb TextWidth is even 268% 269% An arbitrary decision is needed if one of the width is even and one is odd_ 270% 271% ooooooooooiiiiiiiiii ReducedFieldWidth is even 272% aaaXbbb rightly behaviour 273% aaaXbbb leftly behaviour 274% 275% oooooooooXiiiiiiiii ReducedFieldWidth is odd (and has a central character) 276% aaabbb rightly behaviour 277% aaabbb leftly behaviour 278 279start_pos(odd(RFW) ,odd(TW) ,_ ,StartPos) :- StartPos is RFW//2 - TW//2. 280start_pos(even(RFW) ,even(TW) ,_ ,StartPos) :- StartPos is RFW//2 - TW//2. 281start_pos(odd(RFW) ,even(TW) ,leftly ,StartPos) :- StartPos is RFW//2 - TW//2. 282start_pos(odd(RFW) ,even(TW) ,rightly ,StartPos) :- StartPos is RFW//2 - TW//2 + 1. 283start_pos(even(RFW) ,odd(TW) ,leftly ,StartPos) :- StartPos is RFW//2 - TW//2 - 1. 284start_pos(even(RFW) ,odd(TW) ,rightly ,StartPos) :- StartPos is RFW//2 - TW//2. 285 286% In case the ResultType (here called PassedResultType) has been left uninstantiated 287% by the caller, clamp it to 'atom' or 'string', possibly by guessing. 288% Note that we demand to have a positive conclusion as to what type to deliver or 289% we complain, unlike in stringy_concat for example, where lack of a positive 290% conclusion leads to non-determinacy, with two solutions delivered. 291 292complete_result_type(Text,Result,PassedResultType) :- 293 has_type(Text,TextType), 294 has_type(Result,ResultType), 295 has_type(PassedResultType,PassedResultTypeType), 296 assertion(member(TextType,[atom,string])), % has already been check_that-ed 297 assertion(member(ResultType,[var,string,atom])), % has already been check_that-ed 298 assertion(member(PassedResultTypeType,[var,atom])), % has already been check_that-ed (also, if atom, it is one of 'atom', 'string') 299 complete_result_type_2(TextType,ResultType,PassedResultTypeType,PassedResultType), % this throws, or fails or succeeds, with PassedResultType instantiated 300 !, % complete_result_type_2 generates choicepoint we don't want! 301 assertion(check_that(PassedResultType,hard(stringy_typeid))). % PassedResultType must be instantiated now! 302 303% ResultType 304% TextType | PassedResultTypeType 305% | | | +-------PassedResultType (may be var on call, as indicated by the preceding arg) 306% | | | | 307complete_result_type_2(atom , var , var , atom ). % Guess: We want PassedResultType (unbound on call) to be the atom 'atom' because the input texts are both atom 308complete_result_type_2(string , var , var , string ). % Guess: We want PassedResultType (unbound on call) to be the atom 'string' because the input texts are both string 309complete_result_type_2( _ , string , var , string ). % Set: We definitely want PassedResultType (unbound on call) to be the atom 'string' because the provided Result is a string 310complete_result_type_2( _ , atom , var , atom ). % Set: We definitely want PassedResultType (unbound on call) to be the atom 'atom' because the provided Result is an atom 311complete_result_type_2( _ , var , atom , _ ). % OK: the result type is specified (atom on 4th arg) but the Result is var, so anything is ok 312complete_result_type_2( _ , string , atom , atom ) :- fail. % FAIL: the result is specified and 'string' but the ResultType is provided and is 'atom' 313complete_result_type_2( _ , atom , atom , string ) :- fail. % FAIL: the result is specified and 'atom' but the ResultType is provided and is 'string' 314complete_result_type_2( _ , string , atom , string ). % OK: the result is specified and 'string' and the ResultType is provided and is 'string' 315complete_result_type_2( _ , atom , atom , atom ). % OK: the result is specified and 'atom' and the ResultType is provided and is 'atom' 316 317has_type(X,var) :- var(X),!. 318has_type(X,atom) :- atom(X),!. 319has_type(X,string) :- string(X). 320 321common_entry_checks(FieldWidth,Text,Result,ResultType) :- 322 assertion(check_that(FieldWidth, hard(integer), hard(pos0int), _{name:"FieldWidth"})), 323 assertion(check_that(Text, hard(stringy), _{name:"Text"})), 324 assertion(check_that(Result, break(var), hard(stringy), _{name:"Result"})), 325 assertion(check_that(ResultType, break(var), hard(stringy_typeid), _{name:"ResultType"})). 326 327% Get OffsetLeft and OffsetRight out of the SettingsDict (if missing, they are assumed 0) 328 329decaps_offset_left_right(SettingsDict,OffsetLeft,OffsetRight) :- 330 get_setting(SettingsDict,offset_left,OffsetLeft,0), 331 get_setting(SettingsDict,offset_right,OffsetRight,0), 332 assertion(check_that(OffsetLeft, hard(integer), _{name:"OffsetLeft"})), 333 assertion(check_that(OffsetRight, hard(integer), _{name:"OffsetRight"})). 334 335% Get CutLeft and CutRight out of the SettingsDict (if missing, they are assumed true) 336 337decaps_cut_flags(SettingsDict,CutLeft,CutRight) :- 338 get_setting(SettingsDict,cut_left,CutLeft,true), 339 get_setting(SettingsDict,cut_right,CutRight,true), 340 assertion(check_that(CutLeft, hard(boolean), _{name:"CutLeft"})), 341 assertion(check_that(CutRight, hard(boolean), _{name:"CutRight"})). 342 343% Get Offset out of the SettingsDict (if missing, it is assumed 0) 344 345decaps_offset(SettingsDict,Offset) :- 346 get_setting(SettingsDict,offset,Offset,0), 347 assertion(check_that(Offset, hard(integer), _{name:"Offset"})). 348 349% Get Prefer out of the SettingsDict (if missing, it is assumed leftly) 350 351decaps_prefer(SettingsDict,Prefer) :- 352 get_setting(SettingsDict,prefer,Prefer,leftly), 353 assertion(check_that(Prefer, hard(member(leftly,rightly)), _{name:"Prefer"}))
Justify a text left,right or center inside a field of fixed width
Homepage for this code
https://github.com/dtonhofer/prolog_code/blob/main/unpacked/onepointfour_basics/doc/README_stringy_justify.md
*/