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    41 

    42 #include "qdynamiccontextstore_p.h"

    43 #include "qpatternistlocale_p.h"

    44 

    45 #include "qtemplate_p.h"

    46 

    47 QT_BEGIN_NAMESPACE

    48 

    49 using namespace QPatternist;

    50 

    51 const SourceLocationReflection* Template::actualReflection() const

    52 {

    53     return this;

    54 }

    55 

    56 DynamicContext::TemplateParameterHash Template::parametersAsHash() const

    57 {

    58     DynamicContext::TemplateParameterHash retval;

    59     const int len = templateParameters.count();

    60 

    61     for(int i = 0; i < len; ++i)

    62     {

    63         const VariableDeclaration::Ptr &at = templateParameters.at(i);

    64         retval.insert(at->name, at->expression());

    65     }

    66 

    67     return retval;

    68 }

    69 

    70 void Template::raiseXTSE0680(const ReportContext::Ptr &context,

    71                              const QXmlName &name,

    72                              const SourceLocationReflection *const reflection)

    73 {

    74     context->error(QtXmlPatterns::tr("The parameter %1 is passed, but no corresponding %2 exists.")

    75                                      .arg(formatKeyword(context->namePool(), name),

    76                                           formatKeyword(QLatin1String("xsl:param"))),

    77                    ReportContext::XTSE0680,

    78                    reflection);

    79 }

    80 

    81 DynamicContext::Ptr Template::createContext(const TemplateInvoker *const invoker,

    82                                             const DynamicContext::Ptr &context,

    83                                             const bool isCallTemplate) const

    84 {

    85     Q_ASSERT(invoker);

    86     Q_ASSERT(context);

    87 

    88     /* We have:

    89      * - xsl:params in the target template (if any) which may provide

    90      *   default values.

    91      * - xsl:with-params in the caller (if any) which provides values.

    92      *

    93      * We need to, for each parameter:

    94      * - If the called template provides no default value and the caller

    95      *   has no value, it's an error

    96      * - If the called template has a default value and the caller provides

    97      *   none, it should be used

    98      * - In any case the caller provides a value, it needs to be used.

    99      *

   100      * Problems to look out for:

   101      *

   102      * - Each xsl:param is in scope for the subsequent xsl:params. Hence,

   103      *   the evaluation of one xsl:param can depend on another xsl:param,

   104      *   and so on

   105      * - The focus for xsl:params is different from the focus for

   106      *   the xsl:with-params

   107      * - The xsl:with-params are not in scope for the xsl:params.

   108      */

   109 

   110     WithParam::Hash withParams(invoker->withParams());

   111 

   112     /**

   113      * Parameters or not, we must in any case create a new stack frame

   114      * for the template invocation since otherwise we will trash our existing

   115      * variables. Hence it's as with calling user functions.

   116      *

   117      * This is especially reproducible with recursive functions.

   118      */

   119     DynamicContext::Ptr newStack(context->createStack());

   120 

   121     /* We have no parameters, and we have no further error checking to

   122      * do in the case of not being xsl:apply-templates, so we need to do nothing. */

   123     if(templateParameters.isEmpty() && (!isCallTemplate || withParams.isEmpty()))

   124         return newStack;

   125 

   126     const DynamicContext::TemplateParameterHash hashedParams(parametersAsHash());

   127     DynamicContext::TemplateParameterHash sewnTogether(hashedParams);

   128 

   129     const DynamicContext::TemplateParameterHash::iterator end(sewnTogether.end());

   130 

   131     for(DynamicContext::TemplateParameterHash::iterator it(sewnTogether.begin());

   132         it != end;

   133         ++it)

   134     {

   135         Expression::Ptr &param = it.value();

   136 

   137         WithParam::Ptr &withParam = withParams[it.key()];

   138 

   139         if(withParam)

   140             param = Expression::Ptr(new DynamicContextStore(withParam->sourceExpression(), context));

   141         else if(!param)

   142         {

   143             /* Ops, no xsl:with-param and no default value to cover up for it.

   144              */

   145             context->error(QtXmlPatterns::tr("The parameter %1 is required, but no corresponding %2 is supplied.")

   146                                              .arg(formatKeyword(context->namePool(), it.key()),

   147                                                   formatKeyword(QLatin1String("xsl:with-param"))),

   148                            ReportContext::XTSE0690,

   149                            this);

   150         }

   151     }

   152 

   153     if(isCallTemplate)

   154     {

   155         /* Find xsl:with-param that has no corresponding xsl:param. */

   156         /* Optimization: candidate for threading? */

   157 

   158         const WithParam::Hash::const_iterator end(withParams.constEnd());

   159 

   160         for(WithParam::Hash::const_iterator it(withParams.constBegin()); it != end; ++it)

   161         {

   162             if(!hashedParams.contains(it.key()))

   163                 raiseXTSE0680(context, it.key(), this);

   164         }

   165 

   166     }

   167 

   168     newStack->templateParameterStore() = sewnTogether;

   169     return newStack;

   170 }

   171 

   172 void Template::compileParameters(const StaticContext::Ptr &context)

   173 {

   174     Q_ASSERT(context);

   175 

   176     const int len = templateParameters.count();

   177 

   178     for(int i = 0; i < len; ++i)

   179     {

   180         const VariableDeclaration::Ptr &at = templateParameters.at(i);

   181 

   182         /* If our value is required, we don't have a default value. */

   183         if(at->expression())

   184         {

   185             // TODO why do we pass in its own type here?

   186             at->setExpression(at->expression()->typeCheck(context, at->expression()->staticType()));

   187 

   188             at->setExpression(at->expression()->compress(context));

   189         }

   190     }

   191 }

   192 

   193 Expression::Properties Template::properties() const

   194 {

   195     return Expression::DisableElimination; /* We're having issues with recursion detection, so this path currently loops infintely. */

   196 

   197     Expression::Properties collect(body->properties());

   198 

   199     VariableDeclaration::List::const_iterator end(templateParameters.constEnd());

   200 

   201     for(VariableDeclaration::List::const_iterator it(templateParameters.constBegin());

   202         it != end;

   203         ++it)

   204     {

   205         if((*it)->expression())

   206             collect |= (*it)->expression()->properties();

   207     }

   208 

   209     // TODO simplify.

   210     return collect & (Expression::RequiresFocus | Expression::IsEvaluated | Expression::DisableElimination);

   211 }

   212 

   213 Expression::Properties Template::dependencies() const

   214 {

   215     return Expression::DisableElimination; /* We're having issues with recursion detection, so this path currently loops infintely. */

   216 

   217     Expression::Properties collect(body->dependencies());

   218 

   219     VariableDeclaration::List::const_iterator end(templateParameters.constEnd());

   220 

   221     for(VariableDeclaration::List::const_iterator it(templateParameters.constBegin());

   222         it != end;

   223         ++it)

   224     {

   225         if((*it)->expression())

   226             collect |= (*it)->expression()->dependencies();

   227     }

   228 

   229     return collect & (Expression::RequiresFocus | Expression::IsEvaluated | Expression::DisableElimination);

   230 }

   231 

   232 QT_END_NAMESPACE