bug fixes and improvements in tensor parser routines

Author: Jutho

src/indexnotation/analyzers.jl

@@ -42,7 +42,7 @@ function decomposegeneraltensor(ex)
     elseif isa(ex, Expr) && ex.head == :call && ex.args[1] == :conj && length(ex.args) == 2 # conjugation: flip conjugation flag and conjugate scalar factor
         (object, leftind, rightind, α, conj) = decomposegeneraltensor(ex.args[2])
         return (object, leftind, rightind, Expr(:call, :conj, α), !conj)
-    elseif ex.head == :call && ex.args[1] == :* && length(ex.args) == 3 # scalar multiplication: muliply scalar factors
+    elseif ex.head == :call && ex.args[1] == :* && length(ex.args) == 3 # scalar multiplication: multiply scalar factors
         if isscalarexpr(ex.args[2]) && isgeneraltensor(ex.args[3])
             (object, leftind, rightind, α, conj) = decomposegeneraltensor(ex.args[3])
             return (object, leftind, rightind, Expr(:call, :*, ex.args[2], α), conj)
@@ -98,7 +98,9 @@ end
 # get all the existing tensor objects which are inputs (i.e. appear in the rhs of assignments and definitions)
 function getinputtensorobjects(ex)
     list = Any[]
-    if isdefinition(ex)
+    if istensorexpr(ex)
+        append!(list, gettensorobjects(ex))
+    elseif isdefinition(ex)
         append!(list, gettensorobjects(getrhs(ex)))
     elseif isassignment(ex)
         if ex.head == :(+=) || ex.head == :(-=)

src/indexnotation/instantiators.jl

@@ -1,8 +1,7 @@
 
 function instantiate_eltype(ex::Expr)
     if istensor(ex)
-        obj,_,_ = decomposetensor(ex)
-        return Expr(:call, :eltype, obj)
+        return Expr(:call, :eltype, gettensorobject(ex))
     elseif ex.head == :call && (ex.args[1] == :+ || ex.args[1] == :- || ex.args[1] == :* || ex.args[1] == :/)
         if length(ex.args) > 2
             return Expr(:call, :promote_type, map(instantiate_eltype, ex.args[2:end])...)
@@ -18,7 +17,7 @@ function instantiate_eltype(ex::Expr)
         throw(ArgumentError("unable to determine eltype"))
     end
 end
-instantiate_eltype(ex) = Expr(:call,:typeof, ex)
+instantiate_eltype(ex) = Expr(:call, :typeof, ex)
 
 function instantiate_scalar(ex::Expr)
     if ex.head == :call && ex.args[1] == :scalar

src/indexnotation/parser.jl

@@ -20,7 +20,7 @@ mutable struct TensorParser
 end
 
 function (parser::TensorParser)(ex::Expr)
-    if ex isa Expr && ex.head == :function
+    if ex.head == :function
         return Expr(:function, ex.args[1], parser(ex.args[2]))
     end
     for p in parser.preprocessors

src/indexnotation/preprocessors.jl

@@ -44,7 +44,9 @@ normalizeindices(ex::Expr) = replaceindices(normalizeindex, ex)
 
 # replace all tensor objects by a function of that object
 function replacetensorobjects(f, ex::Expr)
-    # first try to replace ex completely
+    # first try to replace ex completely:
+    # this needed if `ex` is a tensor object that appears outside an actual tensor expression
+    # in a 'regular' block of code
     ex2 = f(ex, nothing, nothing)
     ex2 !== ex && return ex2
     if istensor(ex)
@@ -54,7 +56,7 @@ function replacetensorobjects(f, ex::Expr)
         return Expr(ex.head, (replacetensorobjects(f, e) for e in ex.args)...)
     end
 end
-replacetensorobjects(f, ex) = f(ex, nothing, nothing)
+replacetensorobjects(f, ex) = f(ex, nothing, nothing) # same reason as lines 48-52.
 
 # expandconj: conjugate individual terms or factors instead of a whole expression
 function expandconj(ex::Expr)

src/indexnotation/verifiers.jl

@@ -76,14 +76,10 @@ function isgeneraltensor(ex::Expr)
         return count == 1
     elseif ex.head == :call && ex.args[1] == :/ && length(ex.args) == 3
         # scalar multiplication
-        if isscalarexpr(ex.args[3]) && isgeneraltensor(ex.args[2])
-            return true
-        end
+        return (isscalarexpr(ex.args[3]) && isgeneraltensor(ex.args[2]))
     elseif ex.head == :call && ex.args[1] == :\ && length(ex.args) == 3
         # scalar multiplication
-        if isscalarexpr(ex.args[2]) && isgeneraltensor(ex.args[3])
-            return true
-        end
+        return (isscalarexpr(ex.args[2]) && isgeneraltensor(ex.args[3]))
     end
     return false
 end
@@ -149,5 +145,5 @@ end
 # test for assignment (copy into existing tensor) or definition (create new tensor)
 isassignment(ex) = false
 isdefinition(ex) = false
-isassignment(ex::Expr) = ex.head == :(=) || ex.head == :(+=) || ex.head == :(-=)
-isdefinition(ex::Expr) = (ex.head == :(:=) || ex.head == :(≔)) && istensor(ex.args[1])
+isassignment(ex::Expr) = (ex.head == :(=) || ex.head == :(+=) || ex.head == :(-=))
+isdefinition(ex::Expr) = (ex.head == :(:=) || ex.head == :(≔))