Loop through multiple lists to get every iterations in R

Question

Hello I have never written in here because I always found an answer to my problems But now I have one and I can't find a way to resolve it. I have several lists with list in them. Every list is a part of a code and I'd like to paste all these lists in order to obtain all the possible combinations.

here is a list example

evaluation <- list()
for(i in 1:length(Dates)){
  evaluation[[i]] <- list(snapshotDate = toString(Dates[i]))
}

Here is a picture of what is in the evaluation list

And here is the final content where i want to "paste" all the list. Where here I choose the 1st list for each.

content <- list(Eval = evaluation[1],
                cont = cont[1], 
                con = con[1], 
                scenario = sce)

The goal at the end is to have a lot of this content(one for each combination of Eval, cont,con and sce) with in each of them one iteration.

One content looks like this

I have 6 eval, 3 cont, 4 con and 1 sce (but they change over time so the code should be generic for this part) and I don't know how i could code this. I tried a loop but I'am unable to get all the combinations. Could someone help me.

Thanks for reading me and I hope I'll get some answers

Edit: Here is my code as asked by @Skaqqs

library(parsedate)# to have date in ISO8601


Days = 4 

CL_list = c(0.99,0.95,0.90)
measuretype = c("relative") 

TimeH = c(10,30,252)

PTF = c("1")


# Prepare Table of evaluations according to number of Days selected
Dates = lst(format_iso_8601(format(Sys.time())))
for (i in 0:Days){
  tmp <- format_iso_8601(format(Sys.Date() - i))
  Dates <- rbind(Dates, tmp)
}

# create Evaluation 
evaluation <- list()
for( i in 1:length(Dates)){
    evaluation[[i]] <- list(snapshotDate = toString(Dates[i]))
}
# create Cont
cont <- list()
for( i in 1:length(CL_list)){
  cont[[i]] <- list(measureType = measuretype[1], confidenceLevel = CL_list[i]) 
  }


# create con 
con <- list()
for(i in 1:length(TimeH)){
  con[[i]] <- list(type = 'connect', timeHorizon = TimeH[i])
}
# create sce 
sce <- list(currency = 'USD', amountScheme = 'quantity', positions = "pos")




content <- list(Eval = evaluation[1],
                cont = cont[1], 
                con = con[1], 
                scenario = sce)

Edit with the 2 screenshots for @Skaqqs How results should look like How it looks like

Answer 1

You could try this. Example data is below

evalL = 1:length(evaluation)
contL = 1:length(cont)
conL = 1:length(con)
sceL = 1:length(sce)

combos <- expand.grid(evalL, contL, conL, sceL)

results <- lapply(1:nrow(combos), FUN = function(x)
  list(evaluation = evaluation[[combos[x,"Var1"]]], cont = cont[[combos[x,"Var2"]]], con = con[[combos[x,"Var3"]]], scenario = sce[[combos[x,"Var4"]]]))
str(results[1:4])
#> List of 4
#>  $ :List of 4
#>   ..$ evaluation: int 1
#>   ..$ cont      : chr "Jan"
#>   ..$ con       : chr "a"
#>   ..$ scenario  : chr "scenario X"
#>  $ :List of 4
#>   ..$ evaluation: int 2
#>   ..$ cont      : chr "Jan"
#>   ..$ con       : chr "a"
#>   ..$ scenario  : chr "scenario X"
#>  $ :List of 4
#>   ..$ evaluation: int 3
#>   ..$ cont      : chr "Jan"
#>   ..$ con       : chr "a"
#>   ..$ scenario  : chr "scenario X"
#>  $ :List of 4
#>   ..$ evaluation: int 4
#>   ..$ cont      : chr "Jan"
#>   ..$ con       : chr "a"
#>   ..$ scenario  : chr "scenario X"

Data:

evaluation <- list()
for(i in 1:6){
  evaluation[i] <- list(i)
}

mos <- c("Jan", "Feb", "Mar")
cont <- list()
for(i in 1:3){
  cont[i] <- list(mos[i])
}

con <- list()
for(i in 1:4){
  con[i] <- list(letters[i])
}

sce <- list("scenario X")

Created on 2021-09-30 by the reprex package (v2.0.1)

Edit:

library(parsedate)# to have date in ISO8601
library(dplyr)

Days = 4 
CL_list = c(0.99,0.95,0.90)
measuretype = c("relative") 
TimeH = c(10,30,252)
PTF = c("1")

# Prepare Table of evaluations according to number of Days selected
Dates = lst(format_iso_8601(format(Sys.time())))
for (i in 0:Days){
  tmp <- format_iso_8601(format(Sys.Date() - i))
  Dates <- rbind(Dates, tmp)
}
# create Evaluation 
evaluation <- list()
for( i in 1:length(Dates)){
  evaluation[[i]] <- list(snapshotDate = toString(Dates[i]))
}
# create Cont
cont <- list()
for( i in 1:length(CL_list)){
  cont[[i]] <- list(measureType = measuretype[1], confidenceLevel = CL_list[i]) 
}
# create con 
con <- list()
for(i in 1:length(TimeH)){
  con[[i]] <- list(type = 'connect', timeHorizon = TimeH[i])
}
# create sce 
sce <- list(currency = 'USD', amountScheme = 'quantity', positions = "pos")

evalL = 1:length(evaluation)
contL = 1:length(cont)
conL = 1:length(con)
sceL = 1:length(sce)

combos <- expand.grid(evalL, contL, conL, sceL)

evalList <- lapply(combos$Var1, function(x) evaluation[[x]])
contList <- lapply(combos$Var2, function(x) cont[[x]])
conList <- lapply(combos$Var3, function(x) con[[x]])
sceList <- lapply(combos$Var4, function(x) sce[[x]])

content <- list(evaluation = evalList, cont = contList, con = conList, scenario = sceList)

Created on 2021-09-30 by the reprex package (v2.0.1)